Human Anatomy - All Lecture Notes
Human Anatomy - All Lecture Notes ZOOL 270
Popular in Human Anatomy
Popular in Animal Science and Zoology
This 35 page Bundle was uploaded by Jessica Schneider on Sunday January 10, 2016. The Bundle belongs to ZOOL 270 at Humboldt State University taught by Michael King in Winter 2015. Since its upload, it has received 55 views. For similar materials see Human Anatomy in Animal Science and Zoology at Humboldt State University.
Reviews for Human Anatomy - All Lecture Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 01/10/16
Anatomy Notes – August 24 th What is Anatomy? The study of structure Closely related to physiology – the study of function We’ll cover physiology very briefly, about what each structure does Our focus is looking at the large picture of anatomy, looking at the whole body/anatomy We’re going to take apart bodies in a reductionist approach to see how it all comes together and operates as a system Course Organization 1) Reasoning & Learning to Learn 2) Anatomical Themes a. Names and Facts Levels of Organization Biosphere Regions of the Earth where organisms can exist Ecosystem Any community and its physical and chemical environment Community The populations of all species that occupy a habitat Population Group of individuals of the same kind/species occupying an environment Multicellular Organism Individual composed of specialized, interdependent cells arrayed in tissues, organs and often organ systems Organ System* Two or more organs whose separate functions are integrated in the performance of a specific task Organ* One or more types of tissues interacting as a structural, functional unit Tissue* A group of cells and intercellular substances functioning together in a specialized activity Cell Organelle Molecule Atom Subatomic Particles * - Areas that our main focus will be on during the human anatomy course th Human Anatomy – August 26 Evolution The continuous genetic adaption of a species to environmental conditions Charles Darwin HMS Beagle - 5 year voyage, 1831 – 1836, sailed around S. America, Africa, Australia and Galapagos Islands Darwin’s 4 Tenets – 3 Observations and 1 Synthesis 1. Variation in Individuals of a Species 2. Environmental Change (Lyell) 3. Differential Survival – Not all Offspring survive (Malthus) 4. Those Variants, best suited to environmental change, survive and reproduce a. The elimination is selective – Natural Selection! Adaptation/Fitness Genetic adaptation of organisms - they “fit” their environmental niche well and reproduce more Evolution has been understood vaguely by farmers before Darwin – artificial selection of the best plants for better crops in future, offspring generations Evolution can be observed in the similar, adaptive morphology of different organisms Bones of the arm are the same in both bats and birds but they function differently (different sizes and densities) Human Anatomy – August 26 th Evolution The continuous genetic adaption of a species to environmental conditions Charles Darwin HMS Beagle - 5 year voyage, 1831 – 1836, sailed around S. America, Africa, Australia and Galapagos Islands Darwin’s 4 Tenets – 3 Observations and 1 Synthesis 1. Variation in Individuals of a Species 2. Environmental Change (Lyell) 3. Differential Survival – Not all Offspring survive (Malthus) 4. Those Variants, best suited to environmental change, survive and reproduce a. The elimination is selective – Natural Selection! Adaptation/Fitness Genetic adaptation of organisms - they “fit” their environmental niche well and reproduce more Evolution has been understood vaguely by farmers before Darwin – artificial selection of the best plants for better crops in future, offspring generations Evolution can be observed in the similar, adaptive morphology of different organisms Bones of the arm are the same in both bats and birds but they function differently (different sizes and densities) Human Anatomy – August 31 st Cell Theory All organisms are composed of cells Cells are the basic unit of life All cells arise from pre-existing cells Eukaryotic Cell Has a nucleus and organelles* *Mitochondria, vesicle, endoplasmic reticulum, etc. Membranes are a key part of this cell! Cell structure and Function Nucleus Control center/CPU of the cell, determines when the cell reproduces Contains genetic material in the form of DNA DNA, which is then composed of smaller units of chromosomes Endoplasmic reticulum “Inside the plasma network” Involved with the synthesis of DNA into organic molecules (specifically proteins and lipids) Golgi Body/Apparatus Involved in packaging molecules for export out of the cell Mitochondrion Energy producer – makes ATP Uses glucose from blood sugar and converts into energy for cell use Vesicle Membrane-bound bubble (containing some kind of substance) Membrane is either formed from the cell membrane itself (to bring things into the cell) or is produced within the cell itself Lysosomes – vesicles filled with digestive enzymes Cell Membrane Transport Cell Membrane Controls passage in and out of the cell Constructed of two layers of phospholipids, lipid “feelers” face each other Molecules that are not lipid-soluble can’t make it through the membrane Complex glycoproteins are also part of the cell membrane, which act as recognizers for which cells are “self” and which are foreign Part of the immune system Require either active or passive transport for molecules to pass through the phospholipid bilayer Active transport requires energy (ATP) to move things through! Tissues Groups of Cells with a common function Epithelial Tissue Attached to hollow organs by a basement membrane No blood vessels (avascular) Mostly cellular *Excretory Glands The epithelial cells “dive down” into the tissue and forms multi- branched tubules Connective Tissue The most common of the tissue types in the body Involved in binding and support as its main function Few cells in an extracellular/non-living matrix Matrix is composed of fibers (collagen) and ground substance (in between the fibers - hard mineral in bone, gel-like substance in ligaments, etc. Muscle and Nervous Tissue Human Anatomy – September 2 nd Tissues (Cont.) Fibroblasts (“fiber cells”) and immune system cells are both found in loose (areolar) CT Muscle Tissue Contractile – all muscles can do is contract and relax! 3 types of muscle tissue Skeletal muscle Associated with the skeletal system for voluntary movement Densely packed muscle fibers, formed from long multi-nucleated muscle cells! Produces a really strong and fast muscle contraction Smooth muscle Involuntary contractions, found around the digestive tract/intestines Sheets of muscles produce slow “waves” of muscle contraction Cardiac muscles Individual muscle cells are pointed at both ends, with a single nucleus for each cell Also involuntary, but the contractions are strong and fast Primarily forms the heart and blood vessels, highly organized like skeletal muscle Nervous tissue Neuron – sends the electrical signal Can be all different shapes and sizes! Multiple branches called “dendrites” that bring information into the neuron’s main body One long branch called the “axon” extends to send information out of the neuron Neuroglia – support cell Multiple types of neuroglia cells function to maintain repair and protect the neurons Organs Membranes The simplest of organs – often only comprised of two tissue types (simple squamous and loose CT) Flat and sheet-like Multiple types of membranes Serous membranes – very thin, transparent membranes that cover organs/maintain their shape and line the inside of the body cavity (like saran wrap) Provide a protective covering for the organs, very slick Mucus membranes – communicate with the external environment, very soft, thick and moist well protected from drying out and prevents bacteria from invading the body! Constructed of various kinds of ET, and loose CT Synovial membranes – line the joint cavities as a soft cushion and lubrication Cutaneous membrane – only the skin is a cutaneous membrane, the most complex and specialized of the membranes skin is also considered a multi-functional organ system! Organ Systems (11) Integumentary – external protection and covering Skeletal – storage medium for calcium Muscular Circulatory/Cardiovascular – transport of nutrients, gases, hormones, etc. throughout the body Lymphatic – transports excess tissue fluid and returns it to circulation Respiratory Nervous – central and peripheral nervous system Endocrine – secrete hormones (signal molecules) directly into the bloodstream Digestive Excretory – cleans the body of metabolic waste Reproductive Integumentary System – The Skin! Functions Protection Temperature Regulation Waterproofing Resisting desiccation of inner organs and water loss Chemical Synthesis Layer of fat located beneath the skin for energy storage, melanin and vitamin production Excretion Removing urea and salts through the skin by sweating Sensory Perception Nerve endings in the skin for touch and temperature Structure 3 layers Epidermis Epithelial tissue – stratified squamous layers Uppermost/external layer of the skin Dermis Connective tissue – dense irregular Hypodermis Appendages of the Skin Anatomy Notes – September 9 th Integument (cont.) Appendages of the Skin Sudoriferous (“Sweat”) Glands Eccrine/Merocrine Small, watery secretion Evaporative Cooling Apocrine Larger sweat gland, only found in the armpits and groin Creamy secretion – production of pheromones (smell hormones) Sensory Receptors See Lab Notes – September 3rd Lines of Cleavage – “Grain” The fibrocartilage is oriented in patterns within the skin – surgeons make incisions following these “grains” to cut as few fibers as possible and leave less of a scar Fascia – Superficial & Deep Fibrous CT Framework of the Body All the fibrous connective tissue in the body is collected into two groups – “superficial fascia” is closer to the skin, while the “deep fascia” is grouped together closer to muscles/organs/bones Skeletal System – 206 Bones Functions Support Protection Mobility Storage Calcium Phosphorous Fat Hemopoiesis Blood Cell Production – RBC in “red marrow” and WBC in yellow marrow”” Bone Tissue See lab notes – September 3 rd Osteocyte – “bone cell” Osteoblast – builds new bone cells Osteoclast – consumes old bone cells Various reasons for this – Calcium access, clean up bone debris around a fracture site, etc. Bone Matrix Fibers – Collagen (35%) Ground Substance – Calcium Phosphate (65%) Very brittle – easy to break! Bone Growth Dynamic – Bone is Metabolically Active Endochondral Ossification – hardening into bone from fetal cartilaginous template 1) Bone starts as a cartilaginous Template 2) Bone collar forms on diaphysis – perichondrium transforms into periosteum 3) Vascularization – blood vessels are penetrating into the developing bone’s medullary cavity (diaphysis is called the “primary center of ossification”) 4) Spongy bone begins to form on the inside of the hollow medullary cavity a. Increase in both size and diameter – osteoclasts consume bone cells on the inside while osteoblasts build up the outside with compact bone 5) Epiphysis ossifies much later than the diaphysis – is still mostly made of cartilage at birth, the two epiphyses are the “secondary centers of ossification”) 6) Epiphyseal plates form as the main areas of growth after the ossification centers form (this is where juvenile humans grow in height during life) a. Cartilage grows first before the bone ossification “catches up”; this is what happens when you stop growing and reach your adult height Anatomy Notes – September 14 th Bone Growth (cont.) Promoted by growth hormones and sex hormones Intramembranous ossification Seen in flat bones (ex. parietal bones of skull, scapula, etc.) Fractures Partial or Complete Partial– does not go all the way through the bone Closed or Open Open – breaks through the skin/is exposed to external Environment Greenstick Often seen in juveniles, bone “frays” because it is not fully mineralized (similar to trying to break a young/living/wet stick) Spiral or Torsion Fracture Fracture spirals up around the shaft Comminuted Lots of little pieces, portion of bone has been crushed Compression Impact Potts Breaking the medial malleolus of the of the tibia and fibula – they shift to one side Stress Fractures – Repetitive Trauma Mostly happens in tibia and tarsals – especially when running (“shin splints”) Pathologic Fractures Fractures that occur because of disease (ex. cancer, rickets causing the bone to weaken and break more easily) Bone Repair 1) Inflammation, swelling at site of fracture a. Formation of a hematoma (blood clot) 2) 1 week – macrophages (“big eaters”) present at site to consume broken cells and pieces and clean up the fracture debris a. Osteoclast – consume bone pieces b. Fibroclasts – consume broken collagen fibers 3) Fibrous callus forms at fracture site a. Made up of fibrocartilage (for increased support/toughness) 4) Periosteum knits itself back together over the callus a. Blood vessels are also repairing themselves during this stage 5) Osteoblasts move in to the soft callus – form compact bone outside, spongy bone inside a. Now the soft callus is called a hard (bony) callus 6) Over time, the lump of the hard callus will be remodeled and made smaller until the bone is similar to how it originally looked prior to the fracture a. This remodeling process is variable –length of time it takes varies from person to person Artificial aids to repair Cadaver Bone Graft Used for comminuted fractures – cadaver bone fills in the missing portion to act as scaffolding for the patient’s cells Occasionally coral implants are used instead of cadaver bone if the latter is unavailable Electromagnetic fields A small EM field develops around a fracture site, helps to direct and orient the bone cells when repairing the bone A small coil of wire is placed at the fracture site under the skin and a current is run through it at various times in order to stimulate growth Articulations – Joints Functional Classification Structural Classification Anatomy Notes – September 16 th Articulations – Arthrology Functional Classification Synarthrosis – “syn = same”, Immovable joint Ex: suture, acetabulum (anywhere two bones are fused together) Diarthrosis – Freely movable joint Structural Classification “What kinds of materials are holding the joints together?” 1) Fibrous a. Suture – short fibers are inter-digitated together b. Syndesmosis – long fibers i. Ex: Interosseous membrane 1. Found between the radius and ulna, and the tibia and fibula 2. Flexible sheet of membrane holds the two bones together but still allows for movement 2) Cartilaginous a. Synchondrosis – cartilage holding bone together i. Ex: Ribs being connected to the sternum by costal cartilage – typically the cartilage is made up of hyaline cartilage (flexibility!) b. Symphysis – tough joint w/ lots of stress has fibrocartilage (strength) 3) Synovial a. Fluid-filled chamber – acts like a cushion, allows for ease of movement and weight distribution in the joint i. Articular capsule – fibrous CT sheath around the entire joint, holds the two bones together and is where most of the joint’s strength comes from ii. Ligament – thickening of the articular capsule’s CT based on amount and areas of high stress iii. Articular cartilage – made up of hyaline cartilage iv. Joint cavity – very small space between the two bones that is filled with synovial fluid v. Synovial membrane – produces synovial fluid! found around the sides of the joint cavity (never in the middle/between the bones 1. Technically this membrane is an incomplete epithelium because it doesn’t fully line the joint cavity! 2. Very difficult to see because it’s so small Movements Flexion / Extension Flexion is a decreasing angle between two bones Extension is an increasing angle between two bones Ex: extending your arm, flexing your leg Abduction / Adduction Abduction – moving away from the midline/ sagittal plane Adduction – moving closer towards the midline/ sagittal plane Ex: adducting your arms away from your body, abducting your fingers into “Spock” position Rotation/Circumduction Circumduction – describing a cone shape - finger Rotation is more like a pivot (move 360 degrees) – shoulder Protraction/Retraction Protraction – moving anteriorly (swinging your arm forward) Retraction – moving posteriorly (swinging your arm backwards) Elevation/Depression Elevation – moving superiorly (closing your mandible – moving your jaw up) Depression – moving inferiorly (opening you mouth – moving your jaw down) Pronation/Supination Pronation – palms down, lying face down on the floor Supination – palms up, laying on your back Pronation causes the radius and ulna to cross over each other (this is why anatomical requires the palms to be face up, so those bones are not crossed!) Inversion/Eversion Inversion – toes pointed horizontally towards each other Eversion – toes pointed horizontally away from each other (heels together – think ballet) Dorsiflexsion/Plantarflexsion Dorsiflexsion – curling your toes upward Plantarflexsion – curling your toes under Synovial Joint Structure Synovial Joint Types Gliding (Plane) Joint – can side in any direction, but are limited in how far they can go (ex: carpal bones) Hinge joint – can only move in one direction (ex: ulna articulating with the trochlea of the humerus) Pivot joint Can move ~360 degrees around a single axis of movement (ex: head of the radius articulating with the ulna’s radial notch) Condyloid joint Two axis of movement (left to right, up and down), allows for circumduction but not rotation! – ex: phalanx articulating with the metacarpals Saddle joint Two U-shapes moving around each other (ex: carpals and metacarpals) Ball and socket joint Multi-axial movement; can move in pretty much any direction it wants (ex: shoulder joint, head) Joint Disorders Spinal Curvature Human Anatomy – September 28 th Muscular System Functions Skeletal Muscle: Skeletal Movement Connection between the Skeletal and Muscular System “Musculo-Skeletal System” – Integration of Systems Protection (of the Inner Organs) Posture/Body Position Heat Generation Muscles are very metabolically active and there’s a lot of muscle in the body Support (of Soft Tissues) Involuntary Muscle: Involuntary Action of the Digestive Tract and Blood Vessels Guard Entrances and Exits to the Body Ex: Sphincters, Mouth Muscle Tissue Skeletal Muscle Long, skinny cells Multinucleate (More than one nuclei) Cells are densely packed into myofibrils All the contractile units are aligned together – leads to striations (banding) in the myofibrils Smooth Muscle Not very organized – myofibrils run in all different directions Skinny muscle cells with double pointed ends (bit of a squashed diamond shape) Fairly unremarkable in characteristics Cardiac Muscle Some level of organization – not as much as skeletal muscle, but mare than in smooth muscle There is very light striation occasionally Intercalated discs are present in between the individual muscle cells Branching is present – muscle cells branch ou to link up with other muscle cells across gaps Special Terminology My-/Myo- = “muscle” Sarc-/Sarco- = “flesh” *Muscle cells = sometime called “muscle fibers” *These terms are only used to refer to features found in muscle cells: Sarcolemma = “cell membrane” Sarcoplasm = “cytoplasm” Sarcoplasmic Reticulum = “endoplasmic reticulum” synthesis of proteins in muscle Levels of Organization Myofilaments are the proteins that are grouped together to form a myofibril Myofilaments consist of actin and myosin Bundles of myofibrils make up a single muscle cell Muscle cells are sheathed in a membrane called the endomysium) Fascicle (muscle cells wrapped together into a bundle by the perimysium) Multiple fascicles are held together in a larger bundle by the epimysium to construct a whole muscle (Perimysium sections off the fascicle bundles within the muscle) Sarcomere – basic unit of contraction Myofilaments and sarcomeres slide together to create a contraction --? And therefore create movement Anatomy Notes – September 30 th Levels of Muscle Organization Myofilaments* Myofibrils Muscle Cells Fascicles (“Fasciculi”) Whole Muscle *Actin and Myosin = Contractile Proteins Sarcomere Basic Unit of Contraction (tiny molecules moving/doing the work of muscle contraction!) Muscle Contraction Sliding Filament Theory – when sarcomeres are all lined up within the muscle cell, banding occurs this banding pattern visibly shortens and lengthens during muscle contraction and relaxation respectively A single sarcomere slides with the “thin” filaments sliding over the “thick” filaments during contraction (the thick filaments don’t change length) Myosin makes up the “thick” filaments, which have “cross-bridges” Actin makes up the “thin” filaments with active sites Those cross-bridges wiggle and bind to the active sites on the actin Myosin cross bridges bend with the stroke, then detach and reattach to the subsequent actin active site This allows the myosin to “step”/move along the actin and therefore allow the sarcomere to slide along Think an old-fashioned typewriter!! When a muscle cells contracts – every single sarcomere contracts at the same time very quickly; it’s all or nothing there’s no “half contractions” But the contraction process doesn’t last very long, so muscle cells have to take over for each other eventually and pick up the slack The brain has to be constantly determining how many muscle cells to fire at a given time to do whatever you want to do Folded membranes present around the Myofilaments this is called the sarcoplasmic reticulum and contains calcium; when calcium is released to flood over the myofilaments – contraction occurs Calcium is then funneled back into the S.P.R and relaxation occurs Neuromuscular Junction Neurons are connected to every single individual muscle cell, and there is a neuromuscular junction between the neuron and the muscle cell Neurons send an electrical signal down to the axon terminal, where neurotransmitters are released (specifically acetylcholine here) into vesicles to cross the synapse to the muscle cell’s membrane (the sarcolemma) Small channels in the sarcolemma are opened up by the presence of acetylcholine, which allows for ions (“charged particles”) to rush across the sarcolemma and generate an “action potential” (electrical signal) across the entire cell membrane and into the cell When this “action potential” reaches the sarcoplasmic reticulum, it signals for calcium to be released initiating muscle contraction Oxygen is carried and stored in muscle cells by myoglobin (causes muscle to be red) Each muscle cell is packed with myofilaments, myoglobins, mitochondria and the sarcoplasmic reticulum (allows for lots of energy to be stored in your muscle cells to use) 1) Action potential travels down neuron to axon terminal 2) Neurotransmitter (“ACH” = acetylcholine) is released and crosses synaptic cleft to sarcolemma 3) Action potential travels across sarcolemma and down into the sarcoplasmic reticulum 4) The SR releases calcium which initiates muscle contraction 5) Sarcomeres contract as myosin “grabs and pulls” actin 6) Calcium reabsorption by SR causes contraction to cease Smooth Muscle Same contractile proteins as in skeletal muscle, but the sarcomeres are arranged differently They’re not organized neatly in rows, instead there are spots where all the sarcomeres meet and form a network (like a beaded pillow) When the sarcomeres contracts, they contract in all different directions and the actin is so long that the muscle can contract more/for a longer time but its not as strong or as fast as skeletal muscle Because smooth muscle is usually in a sheet, you get a slow wave of contraction moving along the entire digestive tract (aka “peristalsis”) and this wave is occurring constantly Smooth muscle has a “latch state”, which means that it can contract for long periods with little energy use and stay contracted for a while’ Cardiac Muscle Relatively organized with lots of myofibrils produces a strong and fast contraction Packed with mitochondria to produce energy for use 24/7 Single nucleus per cell and is involuntary heart rate/contraction changes because of need (ex: running fast) not because you specifically want it to Intercalated discs between individual muscle cells and there is branching between cardiac muscle cells All the cells are “electrically connected” – an action potential passes from one cardiac muscle cell to the next without pause; allowing for waves of contraction in cardiac muscle to pump blood through the vessels Anatomy Notes – October 5 th Finish Muscular System Electrical signal travels down the neuron to the muscle junction electric signal is turned into a neurotransmitter so it can cross the neuromuscular junction and into the sarcolemma Signal causes an all-or-nothing contraction in the muscle with the release of calcium from the sarcoplasmic reticulum – however we can have a graded contraction through the use of motor units Motor unit – one neuron and all the muscle cells that it innervates; can be any size depending on the need! Motor units do not actively divide like regular cells; you’re born with basically a set amount If you need to lift something light – only one motor unit will be activated, and then another single motor unit will activate to “trade off” If you need to lift something heavy – multiple motor units will be activated at the same time Cardiac muscle doesn’t have a neuron near it like in skeletal and smooth muscle to transmit an electrical signal Cardiac muscle has a “leaky” cell membrane, so ions are constantly coming into the muscle cell slowly, until enough ions have entered the cell to initiate an action potential on its own – “auto-rhythmicity”! Cardiovascular System Function – To assure the needs of every cell are met Transport Water and Electrolytes (Ions) Nutrients (From the Digestive Tract *Processed in Liver* Every Cell) Gases – Bring in O2 and Remove CO2 (Uses Hemoglobin in blood to do this) Metabolic Waste – Urea Kidneys Hormones – Signal molecules carried by blood Enzymes – promote and speed up chemical reactions Maintenance of Homeostasis Homeostasis – “stable internal conditions” Regulating temperature, pH, fluid and electrolyte balance Protection Blood Clots – prevent us from “springing a leak” Immune System – protection from pathogens Basic Flow Pattern 2 Separate Circuits – very efficient blood oxygenation system! Systemic Circuit – carries blood throughout the entire body Pulmonary Circuit – carries blood through the lungs and back to the heart Left side of the heart is very strong – lots of muscle b/c it is the systemic side to pump blood throughout the body Ventricles contract at the same time – each circuit has to pump the same amount of blood at the same time (to prevent buildup and explosions D:>) Heart Location in chest Located in it’s own cavity – the pericardial sac with a serous membrane lining Small amount of serous fluid is present around the heart in the pericardium to allow for friction-free beating The pericardium is located within the mediastinum (which is between the pleural cavities) Heart is pretty much dead center in the middle between the lungs, but the left side of the heart is very large so it bulges out to the left side Blood Flow Septa Great Vessels Inferior Vena Cava Brings in deoxygenated blood from everywhere in the body below the heart Superior Vena Cava Brings in deoxygenated blood from the body above the heart *Both come into the right atrium Pulmonary Arteries Carries blood from the heart to the lungs to be oxygenated Pulmonary Vein Carries freshly oxygenated blood from the lungs back to the heart Enters the left atrium (Blood flows through to the left ventricle Aorta Pumps blood out of the heart and through to the rest of the body Anatomy Notes – October 7 th Cardiovascular System Structure of the Heart Upper two chambers = atria Lower two chambers = ventricles Great vessels of <3 Superior vena cava Inferior vena cava Pulmonary trunk bifurcates into two pulmonary arteries Pulmonary vein – returns oxy. blood from lungs into left atrium Aorta – pumps blood through the systemic circuit Ascending and descending aorta Aortic arch Blood vessels on surface of heart Myocardium – “heart muscle” and these small blood vessels are providing blood flow specifically to the cardiac muscle cells of the heart Heart is lined inside with a serous membrane that prevents the blood from clotting and keeps it flowing smoothly – this membrane is called the “endocardium” Heart has an exterior serous membrane as well to allow the heart to beat friction-free = “epicardium” Septa of the <3 Separating the various chambers of the heart internally – named for its location Atrioventricular septum Between the two atria on top and two ventricles on the bottom Runs more or less horizontally and holds all the valves in place – made of tough CT Fibrous CT acts as an electrical insulator as well – stops the natural progression of an electrical signal through the heart (controls when the heart stops contracting) Interventricular septum Between the ventricles, makes up one side of both ventricles so it’s very thick Interatrial septum – between the atria Valves Atrioventricular valves Very large, found on the left and right – run between the atria and ventricles Right atrioventricular valve aka “Tricuspid valve” = “three flaps” (of tissue) Left Atrioventricular valve aka “Bicuspid valve” or “mitral valve” Chordae tendineae (tendonous chords) Pulling on the flaps of the cusps to prevent them from “blowing out” and opening up when they’re not supposed to These tendons are connected to small papillary muscles below the actual valve Semilunar valves (aortic and pulmonary) Found at the bases of the great vessels Prevents backflow of blood into the ventricles when the heart relaxes Found at the base of the pulmonary trunk and the aorta Walls of the <3 Needs to maintain its shape despite the heart’s rhythmic contracting and relaxing Wall has small trabeculae of cardiac muscle protruding and crossing the inside of the heart’s chambers to keep the heart’s shape Blood Flow through <3 – Cardiac cycle Right atrium Takes in deoxygenated blood returning from systemic circuit Has a very weak contraction, but it has enough power to fill up the right ventricle without overflowing Right ventricle Pumps blood up into the pulmonary circuit) Builds up pressure during ventricular contraction, closing the tricuspid valve until the blood is forced through the semilunar valve into the pulmonary trunk After the ventricle has contracted as much as possible, it relaxes and blood is prevented from back flowing by the closed pulmonary semilunar valve– keeps blood in the pulmonary truck (maintains blood pressure) Left atrium Oxygenated blood returns to the heart from lungs Blood flows into the left atria through the pulmonary veins Weak contraction as well, but has enough strength to fill up the left ventricle Left ventricle Pumps oxy. blood out of heart and back into systemic circuit Ventricle contracts as much as possible (left ventricle = very strong!) to send blood through the aorta and into the body **Both sides of the heart have similar processes occurring at the same time to maintain pressure (and not explode) Volume in all the chambers is the same – they are just shaped differently! Coronary Circulation Coronary artery Provides oxy. blood to the myocardium from the base of the artery Two coronary arteries – one going left and one going right Cardiac veins Pick up deoxy. blood from the heart muscle, take it back behind the heart and dump it into the coronary sinus (blood-filled hollow – pretty much a giant vein) Coronary sinus Drains the deoxy. blood into the right atrium – blood goes back into general circulation then **Aorta Coronary arteries Myocardium Cardiac veins Coronary sinus Right. Atrium Heart as a pump Systole – contraction Diastole – relaxation AV valves are opened, blood flows into the atrium and into the ventricle Atria contract – blood is forced into the ventricles and fills them up Ventricles contract and pressure builds up – semilunar valves are open and blood is forced throughout both the pulmonary and systemic circuits *Cycle repeats itself with the heart relaxing again Human Anatomy Notes – November 2 nd Nervous System Function Main Control System of the Body Specializes in swift but brief responses to stimuli Overview of functional organization Nervous System (NS) Peripheral Nervous System (PNS) Everything outside of the CNS Somatic Conscious control Sensory – info coming in to the CNS SS – “Somato Sensory” SM – “Somato Motor” Motor – info going out of the CNS Autonomic Unconscious control Ex: heart rate, digestion, production of gametes Parasympathetic Division “Fight or Flight” responses Sensory (VS – viscero-sensory/”sensory from the internal organs”) Motor (VM – viscero-motor) Sympathetic Division “Rest and Recuperate” responses Occurs after the “fight or flight“ responses Heart rate slows, digestion increases Sensory (“VS”) Motor (“VM”) Central Nervous System (CNS) Brain Spinal cord Main parts of the brain Hindbrain Pons Medulla oblongata Cerebellum Midbrain Forebrain Cerebrum Thalamus Hypothalamus Human Anatomy Notes – November 30 th Digestive System Structures “Tube-within-a-tube” construction Oral Cavity – salivary glands – pharynx – esophagus – esophageal sphincter – stomach – pyloric sphincter – duodenum – liver – gallbladder – pancreas – jejunum – ileum – ileocecal valve – cecum – colon (ascending/transverse/descending/sigmoid) – rectum – anus Amylase – enzyme that breaks down the starches In carbohydrates into sugars; found in saliva as one of the first parts of digestion Mucosa – innermost mucus membrane that faces the lumen of the intestines Submucosa – mostly connective tissue Muscularis – muscular layer comprised of two layers (inner – circular muscle, outer – longitudinal muscle) Serosa – serous membrane that is the outermost layer of the digestive tract Visceral peritoneum – specific name for the serosa membrane covering the internal organs Parietal peritoneum – serosa membrane lining the internal body cavity Serosa is a continuous double layer of a membrane, so sandwiched between the two membranes is where all of the blood vessels, nerves and so on travel though to get to the intestines Specific concentration of these layers varies depending on where you are in the digestive tract Esophagus has a reduced mucosa and a thicker muscularis layers because peristalsis occurs here to move food downwards into the stomach Stomach has a vey thick muscularis and mucosa layer – hydrochloric acid and other enzymes are produced and secreted into the stomach by the mucosa layer Stomach has an additional oblique muscularis layer in the stomach, as well as the circular and longitudinal muscularis layers, for added strength during digestion Stomach is thicker-walled near the bottom and thinner- walled near the top, so most mechanical digestion occurs at the bottom of the stomach while the top of the stomach is mostly used as storage of excess food (aka after a large meal) Greater omentum – covers the stomach and intestines as a protective layer and fatty insulation layer Pancreas – produces and secretes pancreatic juices that neutralizes hydrochloric acid from the stomach as it enters the small intestine so it doesn’t burn a hole through the intestinal wall Gallbladder – stores bile that is produced in the liver, helps to emulsify fat for digestion within the duodenum Large intestine – divided into small pouches called “haustra” that help form feces and reabsorb water Herbivores typically have a longer large intestine and a longer cecum (cecum as as a fermentation chamber to break down cellulose in plant matter) than carnivores Carnivores eat meat, which is easily digestible, so they have a very reduced cecum and a short large intestine Humans as omnivores fall in between these two systems nd Anatomy Notes – December 2 Excretory System Functions Water and Electrolyte balance (Concentration of electrolytes in human is body ~ 290 mili-osmoles) pH regulation – removal of hydrogen ions (H+) or carbonate ions (HCO) Excretion of metabolic waste and foreign materials Such as environmental toxins, some drugs, human-made molecules saccharine, sodium benzoate, etc. All vertebrates need to get rid of nitrogenous wastes from their body – this can be toxic if it builds up too much Simplest molecule that you can make from nitrogenous amino groups is ammonia Fish do this by releasing ammonia directly into the water through their gills Mammals, amphibians and sharks produce urea Urea is a much more stable molecule and isn’t as toxic – you can have urea build up and be stored in large amounts within the body until it can be released later without dying Birds, insects, reptiles don’t produce urea because it requires a lot of energy and water, and because stored urea increases body weight They make uric acid instead! Production of Renin and Erythropoietin Hormones! Renin – maintains water and electrolyte balance Erythropoietin – increases production of RBCs! Structures Nephron – functional unit of the excretory system! Processes Filtration Occurs at the glomerulus (just a bunch of really leaky capillaries) and blood plasma is leaking out of the capillaries here and then reabsorbed by the nephron tubules This fluid produced by the glomerulus is called the filtrate Treatment of the filtrate is then done in two steps Reabsorption Bringing the good stuff from the blood plasma (amino acids, glucose, water, salts) back into the blood stream Secretion Actively transporting the metabolic wastes out of the blood stream and into the filtrate so that it is removed from the body Reabsorption is typically done through diffusion, however there is some active transport as well The filtrate, after it has been treated, is now considered to be urine Technically, urine is the only thing we excrete from the body! Feces is eliminated from the body because it’s getting rid of indigestible food waste Podocytes cover up the capillaries in the glomerulus and they can open and close to control the rate of filtration for the blood plasma Regulation System of the Nephron The distal tubule of the nephron passes through the blood vessels that supply the glomerulus – here there are specialized cells that analyze the concentration of the filtrate in the tubule and determine bodily needs These specialized sensory cells have a direct connection to the podocytes in the glomerulus and can affect the rate of filtration depending on the amount of fluid loss happening in the filtrate Reproductive System Function Produce new individuals so that the species persists beyond the lifespan of an individual Requirements 1. Production of Gametes “gametogenesis” This occurs in the testes and ovaries 2. Provide for the union of gametes Humans – internal fertilization! 3. Protection of the Developing Individual *Reproductive System is the only system that doesn’t promote individual survival of the adult! Male Reproduction Spermatogenesis – production of sperm Occurs in the seminiferous tubules of the testis Maturation of sperm occurs in the epididymis Anatomy Notes – December 7 th Male Reproduction (cont.) Semen = Sperm & Accessory fluids Function of the fluids to protect and provide energy to the sperm As the sperm travels up through the epididymis and ductus deferens, the spermocyte is in suspended animation and is moved through the tubules by peristalsis and ciliary movement– when accessory fluids are introduced, the sperm is “activated” and begins to swim Accessory Glands Seminal Vesicles Produces fructose, the fuel for spermocytes to swim! Prostate Produces antibiotics, protects sperm from being eaten by any bacteria present in the environment or in the female Microflora in the female’s vagina makes it somewhat acidic to protect it from harmful pathogens, but this acidity also kills the sperm! Bulbourethral Glands Alkaline buffers (to neutralize the acidity of the female and protect the sperm from being killed) as well as mucus to act as a natural lubricant Spermatic Cord Structure The aponeurosis from the inguinal canal and the internal oblique muscle is pushed out from the abdominal wall and is continuous as it wraps around the testes to form the scrotum This continuation of the internal oblique muscle is called the cremaster muscle – making it a skeletal muscle, but it also moves under subconscious control in response to external and internal temperatures! Descent of Testes Testes develop right below the kidneys in the fetus A piece of contractile tissue called the gubernaculum is connected to these developing testes It only contracts once! – Its contraction in the fetus draws the testes and epididymis downwards into the scrotum This also draws the ductus deferens down too, giving the male reproductive system its distinctive path of looping around the urinary bladder and ureters After this single contraction, the gubernaculum degenerates into connective tissue! Female Reproduction Oogenesis in ovaries Oocyte develops in a follicle within the ovary so that it has enough nutrients to grow! This is because an oocyte is much larger than normal cells and has special requirements! Meiosis occurs normally during oogenesis but has an uneven division! At the end of meiosis, only one of the haploid daughter cells will develop into a functional ovum The other three haploid cells are non-functional and degenerate into polar bodies Their only purpose is to remove the excess genetic material produced during meiosis Oocytes are much larger than other cells because it has all of the organelles and nutrients necessary for laying down the “building blocks” required for creating a new individual The male contribution to fetal development is very small in comparison – they only provide the other half of the genetic material, which is why they can create millions of sperm every day since the energy output required to make sperm and release them by the thousands during ejaculation is tiny!! Ovarian Cycle Follicular phase Development of the oocyte in a follicle within the ovary – duration of ~14 days FSH is produced by the anterior pituitary gland and stimulates the follicle to begin the ovarian cycle Ovulation Thinning between the follicle and the ovarian wall hydraulic pressure within the follicle ruptures it and pushes the oocyte out of the ovary Oocyte has a protective coat called a “corona” to protect it while it free-floats outside of the ovary until it is picked up by the infundibulum of the uterine tube Luteal Phase – duration of ~14 days The ruptured follicle becomes a very “fluffy”, glandular structure called a corpus luteum in the ovary that produces estrogen and progesterone eventually it slowly degenerates if implantation of the oocyte hasn’t occurred LH stimulates ovulation and the initiation of the luteal phase Internal Structures Uterus Myometrium – exterior, very thick muscular wall of the uterus Endometrium – inside wall of the uterus – very glandular and rich in nutrients! Cervix – opening at the bottom of the uterus External Structures Vagina Has folds called “rugae” within it that allow for expansion during labor Opening may or may not be covered by a membrane called the hymen during prepubescence– very easily to rupture (alternatively can be very tough to break which is bad Labia minora – internal, mucus membranes Labia majora – external, skin flaps Clitoris Anatomy Notes – December 9 th Female Reproduction (cont.) Uterine Cycle (*See Lab 12/8 notes*) Huge surges of estrogen, then LH and finally FSH initiate ovulation – where the secondary oocyte is expelled out from the ovary-bound follicle LH in males promotes production of male sex hormones (androgens) –produced by the interstitial cells in the testes and seminiferous tubules Homologous Structures Arise from the same primordial during development Initially, male and females are not physically different until ~10 weeks At first, we all look physically female – a surge of male hormones are produced based on the embryo’s genetic code in order to make it male Males = Females Scrotal sacs = labia majora Glans penis = glans clitoris Bulbourethral glands = greater vestibular glands Development Secondary oocyte is almost always picked up and drawn into the infundibulum of the uterine tube Secondary oocyte has not undergone meiosis 2 yet! If sperm are present, and manage to digest the corona enough for one sperm to fuse with the ova’s cell membrane, then the ova’s cell membrane changes to prevent any other sperm from getting in Nuclear fusion occurs between the nucleus of the sperm and the nucleus of the ova to result in a new genomic code for an individual This fused nucleus is called a zygote and is now in the single cell stage Cleavage immediately happens to turn the zygote from one cell to two cells The zygote remains the same size as it was in the one cell stage though, it isn’t actually growing in size! This is all happening as the zygote travels through the uterine tube and is picking up nutritious secretions from this region that are just enough to satisfy the energy requirement of cleavage Implantation By the time the zygote has entered the uterus from the uterine tube, it has cleaved so much that it is now a solid ball of cells called a morula The morula then inverts and becomes a hollow ball of cells called a blastocyst Now there’s no issue in getting nutrients to all of the cells in the blastocyst and it imbeds itself in the uterine wall by eating its way into the nutritious endometrium The blastocyst can now begin to grow in size and develop multiple tissue layers and other organs The entire implantation process lasts about 14 days and at the end of it, the placenta of the implanted blastocyst produces human chorionic gonadotrophy (HCG) HCG causes the corpus luteum to persist and continue making estrogen and progesterone If the corpus luteum degenerates before the embryonic placenta is formed, then the blastocyst will not be able to survive in the uterus Placenta This is the first organ developed by the embryo as it develops from a blastocyst! The placenta is composed of fetal capillaries that are surrounded by pools of maternal blood Developing fetus gets nutrients from the food its mother consumes during pregnancy directly from her bloodstream Maternal and fetal blood is separated by the capillaries, and the only time the blood intermingles is during birth when the placenta detaches from the uterine wall Parturition Surge of estrogen from the ovaries induces oxytocin receptors on the uterus Oxytocin that is produced by the maternal and fetal pituitary glands stimulates the uterus to contract in a large wave Also stimulates the placenta to make prostaglandins These induce more contractions in the uterus, which makes more oxytocin and prostaglandins! This is an example of a positive feedback loop!
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'