BIO 253 Week 6 Notes
BIO 253 Week 6 Notes Bio-253-06
Popular in Human Anatomy and Physiology
Popular in Human Anatomy and Physiology I, Biology
This 8 page Class Notes was uploaded by Talia Ali on Sunday October 16, 2016. The Class Notes belongs to Bio-253-06 at Jackson College taught by Proefessor Brandon Cooley in Fall 2016. Since its upload, it has received 2 views. For similar materials see Human Anatomy and Physiology in Human Anatomy and Physiology I, Biology at Jackson College.
Reviews for BIO 253 Week 6 Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 10/16/16
Jackson College Fall Semester 2016 Professor: Mr. Brandon Cooley Anatomy and Physiology 1 Cell Structure and Function ___ Notes Introduction: The Cellular Level of Organization Here are some quick facts that you will need to know. The human egg is the largest cell in the body. The body itself contains 100 trillion cells. The study of the cell is clled cytology. The study of the cell functions is called cell phsiology. Introduction: Generalized Cell Structure The plasma membrane is the outer boundary of the cell. The cytoplasm of a cell is what’s in between the membrane and the nucleus and it is made up of: ● Cytosol - the fluid in the cell. ● Organelles - small organs. The plasma membrane holds the cell’s contents in and keeps unwanted intruders out. The plasma membrane is made up of a phospholipid bilayer. Every membrane in the cell has the same structure. The Fluid Mosaic is what happens when many tiny pieces are embedded together in the phospholipid layer. The membrane lipids are: ● Phospholipid Bilayer - Makes up 75% of the lipid content in the membrane and has a hydrophilic polar head and a hydrophobic nonpolar tail. ● Glycolipids - Made up of carbohydrates and fats. ● Cholesterol - Is a steroid and an alcohol group that consists of -OH (hydroxide) and gives strength to the membrane. The membrane proteins give needed strength to the membrane. The membrane acts as a channel, transports things into and out of the cell, can act as a receptor, has enzymes, holds the cytoskeleton in place, and also identifies other cells. There are two types of membrane proteins. These are: ● Integral - Move in and out of the cell and create tunnels. These are mostly made up of glycoproteins. ● Peripheral - Live in the surface of the cell either internally or externally and are not tightly attached to any one part of the cell. Glycocalyx functions as a foreign cell recognition tool and is made up of glycolipids and glycoproteins. Introduction: Functions of the Cell Membrane The cell membrane provides the cell with structural integrity, communication between cells by use of chemicals, hormones, enzymes, antibodies, and also uses identifying markers on cells for recognition. The cell membrane is also selectively permeable, which means that it chooses what it allows to enter into the cell and what it won’t allow into the cell. If the membrane is permeable to a substance, then it will allow it inside the cell. The membrane also establishes an electrochemical gradient, especially neuron and muscle cells. Membranes are charged due to their concentration of ions on the interior vs their exterior. The voltage difference is called the membrane potential or electrical potential. The inside of a membrane is negative compared to the outside. Potential energy in the membrane is stored as cation concentration gradient on the outside of the cell membrane. Introduction: Transport Across the Plasma Membrane Passive process in the membrane means that the cell doesn’t have to produce energy to allow substances into the membrane or take substances out. Examples of passive transport are as follows: ● Simple Diffusion - Moving atoms from an area of high concentration to an area of low concentration. This is used for: ○ Gases, fatty acids, steroids, and fat soluble vitamins. (A,D,E,K) ● Facilitated Diffusion - Parts of the membrane that accelerate diffusion. This is used for: ○ Glucose ● Osmosis - Water passing through the membrane. It is a high to low concentration. Thermal heat energy is a factor for the rate of osmosis. Osmosis occurs through: ○ Aquaporin Water Channels The active processes in the cell membrane happens when the cell has to use its energy to transport something through the cell membrane. Energy can be received from hydrolysis. Energy is usually needed because what’s being moved is large and or goes against the gradient. Primary active transport uses an ion transport pump, which is a protein in the membrane that exchanges ions. PAT is useful for the maintenance of a membrane potential, most importantly in neuron and muscle cells, and it is also vital for balancing water within cells. Secondary active transport uses the differences in the concentration of ions to move substances across the membrane. This is used for transporting: ● Glucose ● Amino Acids ● Other Monosaccharides Vesicular Transport moves larger amounts of materials using energy. A vesicle is a container that holds items that are endocytosed, or within the cell. Endocytosis is the transport of substances into the cell. There are two types of endocytosis: ● Phagocytosis - Solid materials such as dead cells ● Pinocytosis - Tiny amounts of liquids Receptor Mediated Endocytosis is what happens when an object attaches itself to a specific spot on the membrane so that the object can be internalized, basically a key that opens a door. xocytosis s transporting a substance out of the cell. Introduction: Tonicity Tonicity is the shape and firmness of a cell as a result of osmosis. Isotonic solution means that the solution is balanced Iso = Balanced) and the solute and solvent are of equal concentration on both sides of the cell membrane. Hypotonic solution means that there is a high solvent to solute ratio. Hemolysis occurs when water enters the cell through osmosis and the cell swells and bursts. Hypertonic solution occurs when there is a high solute to solvent ratio, e.g low salt, a lot of water. Crenation is when water leaves the cell, causing the cell to shrivel. Bulk Flow/Filtration happens when water and the solutes dissolved in water are forced through membranes because of pressure caused by the heart. Introduction: Cytoplasm Cytoplasm is the contents of a cell. There are always changes and fluctuations in the cytoplasm. Cytosol is a fluid and is colloidal, which means that organelles won’t dissolve in the fluid. Organelles are structures inside the cell that each have a certain function. Introduction: Organelles Within the Cell The cytoskeleton is the support framework within the cell and is made up of proteins. Inside the cytoskeleton are: ● Microfilaments - Made up of actin, and in muscle cells, microfilaments help with contraction. ● Microvilli - Extensions inside the cytoskeleton that increase surface area and are supported by microfilaments. ● Intermediate Filaments - Proteins that hold organelles in place. ● Microtubules - Tracks intracellular movement. Centrosomes and centrioles organize and separate chromosomes during cell division and produce the spindle for when the cell divides. Inside the centrosome are two centrioles. Centrioles create flagella and cilia. Cilia are microtubules that are like little fingers that surround the cell membrane. M ove and push things along. They can be found on: ● The lining of the reproductive tract. ● The apical surface of epithelial cells. ● Inside the lungs. Flagella are like little tails ropel cells forward. These can be found on: ● Prokaryotic cells ● Sperm cells Ribosomes are groups of RNA that c reate proteins. The rough endoplasmic reticulum processes proteins and create glycoproteins and phospholipids. The smooth endoplasmic reticulum creates lipids and carbohydrate although in muscle cells these are called sarcoplasmic reticulum and they s tore calcium ions. The golgi apparatus changes, organizes, and packages proteins that come from the rough ER and transports them to various areas in the cell ysosomes destroy debris and bacteria as well as organelles using digestive enzymes. Peroxisomes remove hydrogen from organic molecules to metabolize or detoxify, and creates and destroys hydrogen peroxide. Proteasomes have proteases that estroy unnecessary proteins. Mitochondria are the powerhouse of the cell, have double membranes, burn organic molecules, and synthesize aerobic cellular respiration to create ATP. Cell inclusions are the abiotic objects in the cell. These include: ● Melanin ● Glycogen - Carb storage inside muscle cells and can be found in the lining of the uterus and vagina. ● Triglycerides - Fats found in adipose tissue. The nucleus can be found in the center of the cell and holds DNA. Parts of the nucleus are: ● Nuclear Envelope - Wraps around the nucleus. ● Nuclear Pores - Channels that choose what can come in and out of the nucleus. ● Nucleolus/Nucleoli - Inside of the nucleus that creates ribosomes. Introduction: Genetic Material Genetic material is made up of: ● Genes ● Chromosomes - 23 pairs in somatic cells ● Chromatin - The thin wispy state of DNA during cell interphase. ● Sister Chromatids - The original and copied half of the chromosome. Gene action and protein synthesis occurs when cells create proteins and the proteins choose what the structure and function of itself will be, and the genes choose the protein. Protein synthesis is when tRNA translates the code of nucleic acids into the amino acid code and creates a protein. Transcription is when instructions from DNA are placed into RNA to create a mRNA strand. The base triplet of DNA happens because DNA and RNA codes occur 3 bases at a time. Messenger RNA moves DNA to the ribosome. Translation happens to nucleic acid code to turn it into amino acid code. Ribosomal RNA are what make up ribosomes. ransfer RNA attaches to a specific amino acid a ransports it to the ribosome to create the proper sequencing of amino acids. Codon and anticodon are 3 base code per 1 amino acid. Codon is on mRNA and anticodon is on tRNA. SOS Genes repair DNA and change it back into its original sequence and most changes are made immediately. Genetic engineering occurs when a damaged gene is removed and replaced with a correct gene. Introduction: Division Within the Cell - Mitosis Cytoplasmic division is equally divided except for in the making of eggs. Another term for cytoplasmic division is cytokinesis, and evidence of cytokinesis can be seen in a cleavage furrow. Somatic cell division, or mit create homologous chromosomes and copies genetic info. The cell cycle from start to end is 19-26 hours, and is mostly interphase. Homologous chromosomes have 23 pairs and are lined up from largest to smallest. One pair is paternal and the other maternal and carry allele iploid cells have a double set of chromosomes in the nucleus and mitosis creates diploid cells (2n). Interphase is when the cell is at metabolic rest and not actively dividing. Interphase is placed into three categories: ● G1 ● S ● G2 The mitotic phase has 4 stages of division: ● Prophase - The nuclear membrane breaks down, the cell spindle forms and chromatids are visible. ● Metaphase - Chromosomes line up along the equator of spindle. ● Anaphase - Chromosomes separate and begin to be pulled apart by the spindle. ● Telophase - Cytokinesis occurs and the nuclear membrane reassembles. Cells have a choice between dying, dividing and growing, or remaining in interphase, and this is called Control of Cell Destin Cyclin -dependent protein kinases ctivate or deactivate enzymes that regulate cell division. Apoptosis is genetically programmed cell death and causes phagocytes to consume and digest the cell. Necrosis is cell death caused by injury to the tissue. Tumor-suppressor genes create proteins that top cell division. Introduction: Division Within the Cell - Meiosis Meiosis is the nuclear division of sex cells such as gametes, egg and or spe aploid is one of each chromosome pair. Spermatogenesis occurs in the testes and produces all 4 n cells. (n = 23 chromosomes). ogenesis occurs in the ovaries and creates a secondary oocyte, is 1 of 4 n cells. A zygote is the cell that is fter fertilization, and mitosis will begin. Sex chromosomes are of the 23rd pair of chromosomes, XX means female, XY means male. Autosomes are pairs 1-22 and are n on-sex chromosomes. Introduction: Cells and Aging Cellular aging and decay occur as a result of the progressive failure of homeostasis. Geriatrics is the caring and studying of the eld Aging Genes in aging cell ill not divide and their cellular activity gets slower over time. Skeletal muscle and nerve cells do not perform mitosis. Telomere shortening is the leading idea for why aging happens, and it states that the tips of chromosomes wear down as they divide which means the wear down of functional genes. The Free Radical Theory is another leading idea for why cells age, and it states that free radicals steal electrons from the body’s functional molecules to react with unpaired electrons. Neoplasm occurs when cells divide out of control Oncology is the study of tumors. There are three types of cancer: ● Carcinoma - Malignant cancer that stems from epithelial cells. ● Melanoma - Cancer inside melanocytes. ● Sarcoma - Cancer in the muscle and or connective tissue. Osteogenic sarcoma is cancer in the bones, and this cancer is most frequent in children. Leukemia is the cancer of blood forming organs, and white blood cells are being destroyed so the immune system is compromised. Lymphoma is the cancer within lymphatic tissue. The initial growth and spread of cancer starts with rimary tumor, and then moves on to become a secondary tumor, which detaches from the area where it began and travels using circulation to get to it’s next site. Hyperplasia is the increase in rate of cell division, and this causes healthy cells to become crowded out. Cancer cells do not have contact inhibition. Metastasis is the spread of cancer through blood and lymph. There are a few possible causes of cancer, which include: ● Carcinogen - Something in the environment that produces cancer. ● Mutation - A permanent change in a gene. ● Oncogenes - Cause noncancerous cells to become cancerous. ● Oncogenic Viruses - Chronic viral infections. ● Carcinogenesis - A progression of gene mutations. The treatment of cancer is hard because by the time the cancer cell divides, many of the different cells impacted respond differently to treatment. To prevent cancer, try to avoid carcinogens, get enough exercise, and eat healthily.