Log in to StudySoup
Get Full Access to University of Louisiana at Lafayette - Class Notes - Week 5
Join StudySoup for FREE
Get Full Access to University of Louisiana at Lafayette - Class Notes - Week 5

Already have an account? Login here
Reset your password

UNIVERSITY OF LOUISIANA AT LAFAYETTE / Biology / BIOL 122 / How does the large intestine absorb water?

How does the large intestine absorb water?

How does the large intestine absorb water?


School: University of Louisiana at Lafayette
Department: Biology
Course: Biology Principle & Issues II
Term: Fall 2019
Tags: Bio, Biology, #bio122, Science, animals, and Hormones
Cost: 25
Name: Biology 122 Week 3 Notes
Description: These notes cover the topics of Plant Hormones & Animal Diversity! These are week 3 notes.
Uploaded: 08/29/2019
9 Pages 113 Views 3 Unlocks

Bio 122 Notes:

How does the large intestine absorb water?

9-23-19 & 9-25-19

Week 5

***Monday we had no notes because we took Exam 1***

o Chemical Digestion Occurs in the Small Intestine: 

 1.) Pancreas releases digestive enzymes that break  

polysaccharides down to simple sugars, or  


 2.) Monosaccharides are actively transported into brush  border cells, then out into interstitial fluid.

 3.) Proteins are broken into polypeptides, then amino acids.  4.) Amino acids are actively transported into brush border  cells, then out into interstitial fluid.

 5.) Movements of the intestinal wall break up fat globules  into small droplets. Bile salts coat the droplets, so that  

globules cannot form again.

What would you predict about the levels of thyroid hormone in the blood of giant pandas compared to other bears?

Don't forget about the age old question of What is endocytosis and exocytosis?

 6.) Pancreatic enzymes digest the droplets to fatty acids  and monoglycerides.

 7.) Monoglycerides and fatty acids diffuse across the  

plasma membrane’s lipid bilayer, into brush border cells.

 8.) In a brush border cell, the products of fat digestion for  triglycerides, which associate with proteins. The resulting  

lipoproteins are then expelled by exocytosis into the  

interstitial fluid inside the villus.

o Large Intestine: Our Microfloral Farm 

 After things pass through small intestine, a large amount of water and nutrients are already absorbed.

 Whatever water, nutrients, and vitamins made by bacteria  that are left are absorbed.

What adaptations are present in its gas exchange organs?

 The bacteria is symbiotic.

 Examples of problems:

 Appendicitis

o If the appendix swells up and clogs with  


o Can burst if swells too much.

 Colon cancer

o Comes in the form of polyps.

 How does the large intestine absorb water?  

o Function of Large Intestine: Absorb Water 

 Also houses microbes that produce vitamins.

 Ex: vitamin K

 Once thought that avoiding drinking cold water and being  cold was a preventative of cholera. If you want to learn more check out What are the elements of public disclosure of private facts?

 Vibrio cholerae produces a toxin that results in pumping of  Cl- into the intestinal lumen.

 Na+ cannot be absorbed, and the high osmotic pressure of  the intestinal lumen draws water into the intestinal lumen.  Patients may produce 6 liters of watery diarrhea each day.  Without prompt treatment, death by dehydration occurs in  a few days.

o Herbivore Adaptations: 

 No animal produces cellulase.

 Only protists and bacteria create this.

 How to eat grass?

 Microbes in compartments upstream of the acidic stomach  digest cellulose.

 Their stomachs contain 4 different stomach chambers.  1.) Food is ingested in esophagus and goes into  

stomach chamber #1.

 2.) The food then passes into stomach chamber #2.  3.) The food is then regurgitated back up the  


 4.) The food is then re-swallowed and goes into  

stomach chamber #3.

 5.) The food then passes into stomach chamber #4  and then out into the small intestine.

 For human molars, we have a long root and the crown is  above the gumline.

 For antelope molars, they have a short root and the crown  is extremely long. Most of their crown is below the gumline.  Saliva of cattle contains high concentrations of urea. Why?  The saliva goes into 1st stomach compartment which  have microbes. We also discuss several other topics like How is light turned into neural signals?

 In non-ruminants (ex: horses or rabbits) the microbes are  housed in the large intestine.

 Bunny rabbits eat their poop. Why

o So that they can digest the microbes

 A horse needs to eat much more hay than a cow.  Why?

o To ingest enough microbes to break down the  

stomach contents.

o Hormones & Gastric Secretion:

 The taste, smell, touch sensation, or thought of food sends  nervous impulses to the brain.

 The nervous impulses cause neurons to stimulate secretion of hydrochloric acid and pepsin into the stomach.

 Feedback control.

o Carnivores & Herbivores: Gut Anatomy 

 Carnivores have

 Stomach

o Looks similar in both carnivores and  


 Small intestine

o MUCH larger than the herbivore’s small  


 Cecum We also discuss several other topics like How far do you generalize a piece of knowledge?

o Very small on carnivores.

 Colon (large intestine)

o Straight on carnivores.

 Herbivores have

 Stomach

o Looks similar in both herbivores and  


 Small intestine

o Much shorter and less condense than the  


 Cecum

o Very long and curled, unlike the carnivores.

 Colon (large intestine)

o Much longer and condensed than the  


- Giant Pandas are in the Order Carnivora, or meat eaters, but they eat  only bamboo plants. Compared to other bears, the panda intestinal  tract is what? About the same length as other bears. 

- Compared to other bears, the metabolic rate of pandas is what? Low. If you want to learn more check out How to calculate a formal charge?

- What would you predict about the levels of thyroid hormone in the  blood of giant pandas compared to other bears? That it is lower in  giant pandas. 

- Animals: Respiration

o Respiration Has Different Levels in Different Animals:  Homo sapiens cannot handle high altitude.

 Because of low oxygen.

 Bar headed goose, Anser indicus, can handle high altitude.

o Not All Animals Have Lungs or Gills: 

 Not all animals have special respiratory surface. If you want to learn more check out What is meant by the phrase “structure equals function”?

 If an animal is thin, they can just take oxygen up with their  skin.

 Examples: sponges, flat worms, & jellyfish.

o Gas Exchange During Respiration: 

 Gas exchange is the process of taking up oxygen and  releasing carbon dioxide from metabolic processes in  


 Not enough oxygen = you won’t live long.

 Respiration serves as a means for the body to exchange  gases with the atmosphere via the blood.

 Some animals use the skin as a gas exchange organ.  Ex: Lungless salamander.

 Skin has to be wet to dissolve gas.

 OK for low oxygen demand.

 Aquatic animals must be thin.

 Some animals get O2 from the atmosphere or from the  water column.

 Ex: Whales.

 Air = 20% O2

 Water = 0.7% O2

- In terrestrial animals, ventilation rate is most sensitive to changes in  what? Blood pH 

- A list of proteins that reversibly bind to O2 are what? Hemoglobin,  Hemocyanin, & Myoglobin. 

o Aquatic Respiration: 

 The amount of gas that dissolves in water depends on the  solubility coefficient and partial pressure of the gas in  

contact with the water.

 Increasing temperature reduces solubility of gases.

 Increasing salinity reduces solubility of gases.

 FW at 15 degrees C contains 7.2 ml O2/L.

 SW at 15 degrees C contains 5.8 ml O2/L.

o Aquatic Gas Exchange Organs: Gills 

 Getting oxygen underwater can be somewhat difficult.

 Examples of creatures that adapted:

 Nudibranch mollusk.

 Larval salamander with external gills.

o Bluefin Tuna (Thunnus thynnus): 

 This animal has a high oxygen demand.

 What adaptations are present in its gas exchange organs? - Fish Gills

o All Fish Gills Have This: 

 Ventilation

 Large surface area

 Flow through

 Counter-current exchange

 Example:

 A.) Bony fish with its gill cover removed. Water flows  in through the mouth, over the gills, then out through  

the gill slits. Each gill has bony gill arches with many  

thin gill filaments attached.

 B.) Two gill arches with filaments.

 C.) Countercurrent exchange: flow of water and blood.  D.) Oxygen flow from water into a capillary. All along  the capillary, oxygen flows down its concentration  

gradient from water into blood.

o Mechanisms of Ventilation in Fish: 

 1.) Mouth opens and the jaw is lowered to draw water into  the buccal cavity. The operculum then pulls away from the  body, expanding the opercular cavity.

 2.) Mouth closes and the lower jaw raises, which squeezes  water toward the opercular cavity. Water is forced across  the gills and out through the open operculum.

 3.) Operculum closes and the cycle begins again.

 A.) Buccal pumping.

 B.) Ram ventilation.

o Saving energy by swimming with mouths open  

to ventilate their gills.

 Ex: tuna.

o Efficiency of O2 extraction in ram ventilators  

approaches 90%.

o Oxygen Availability on Land:

 As the meters above sea level increase, the atmospheric  pressure decreases.

 At sea level there is more oxygen than at the top of Mt.  Everest.

 Less than half of what is at sea level.

 Terrestrial animals: desiccation is a problem

- Insect Tracheal System

o Insect Tracheal System Contains: 

 Trachea (tube inside body).

 Spiracle (opening to body surface).

 The tracheal system is part of the exoskeleton and is shed  during molts.

o Respiratory Organs of Terrestrial Animals Vary: 

 Land snail: vascularized skin inside mantle cavity.

 They have blood supply inside mantle to take up  


- Does a frog or a snake use their skin for gas exchange? A frog. - Lungs

o Human Lungs Execute This for Success: 

 Tidal ventilation.

 Mucus cilia for cleaning.

 Surfactants prevent alveolar collapse.

o Human Lungs Contain: 

 Oral Cavity (mouth)

 Supplemental airway when breathing is labored.

 Pleural Membrane

 Double-layer membrane that separates lungs from  

other organs; the narrow, fluid-filled space between  

its 2 layers has roles in breathing.

 Intercostal Muscles

 At rib cage, skeletal muscles with roles in breathing.  

There are 2 sets of intercoastal muscles (external and  


 Diaphragm

 Muscle sheet between the chest cavity and abdominal cavity with roles in breathing.

 Nasal Cavity

 Chamber in which air is moistened, warmed, and  

filtered, and in which sounds resonate.

 Pharynx (throat)

 Always connecting nasal cavity and mouth with  

larynx; enhances sounds; also connects with  


 Epiglottis

 Closes off larynx during swallowing.

 Larynx (voice box)

 Airway where sound is produced; closed off during  


 Trachea (windpipe)

 Airway connecting larynx with 2 bronchi that lead into the lungs.

 Lung (one of a pair)

 Lobed, elastic organ of breathing; site of gas  

exchange between internal environment and outside  


 Bronchial Tree

 Increasingly branched airways starting with 2 bronchi  and ending at air sacs (alveoli) of lung tissue.

o Mechanism of Ventilation in the Human Lung: 

 2 sets of muscles involved:

 Diaphragm.

 Intercostal muscles.

 A.) Inhalation

 Diaphragm contracts, moves down.

 External intercostal muscles contract, life rib cage  

upward and outward.

 Lung volume expands.

 B.) Exhalation

 Diaphragm, external intercostal muscles return to  

resting positions.

 Rib cage moves down.

 Lungs recoil passively.

- Gas Exchange in Birds

o Birds Contain: 

 Posterior air sacs.

 Lungs.

 Scanning electron micrograph of a bird lung tissue  

shows tubes through which air flows to and from air  


 Anterior air sacs.

o Schmidt-Nielsen Figures Out What Air Sacs Do: 

 Hypothesis

 Avian air sacs direct the flow of air through the lungs.  Key Materials

 Ostriches, gas analyzer, & oxygen tank.

 Experiment 1

 Analyze gas contents in anterior and posterior air  

sacs, using an air-sampling syringe.

 The Data Results from Experiment 1

 The researchers proposed that air moves directly to  posterior sacs, then through the lungs, and then to  

the anterior sacs.

 Anterior air sacs= low O2 & high CO2.

o Air sac has been passed through the lungs.

 Posterior air sacs= 21% O2 & low CO2.

o Air sac hasn’t been passed through the lungs.

 Experiment 2

 Give ostriches a single breath of pure O2, which can  be tracked as it moves through the respiratory  


 Then remove the mask and allow the bird to breathe  normal air.

- Terrestrial Animals

o Control of Ventilation: Terrestrial Animals 

 Blood pH controls the rate of ventilation.

 Ex: Hyperventilating makes the pH higher (more  


 CO2 + H2O = H2CO3 (carbonic acid) = H+ + HCO3-.  Makes blood acidic.

 Stimulus

 CO2 concentration and acidity rise in the blood and  

cerebrospinal fluid.

 Response

 Tidal volume and rate of breathing change.

 CO2 concentration and acidity decline in the blood  

and cerebrospinal fluid.

o Respiratory Proteins: 

 We need proteins that carry oxygen from lungs to tissues.  2 main proteins.

 Hemoglobin.

o Red.

o Uses iron to bind oxygen

 Hemocyanin.

o Blue.

o Found in arthropods (but not in insects).

 These proteins increase O2 carrying capacity of  

hemolymph in the blood.

- Anatomy of an Alveolus

o Surface View of Capillaries Associated with Alveoli Contain:  Cutaway view of one alveolus and adjacent pulmonary  capillaries.

 Has pore for air flow between adjoining alveoli.

 Has red blood cells inside pulmonary capillary.

 Has air space inside alveolus (very thin).

 Three components of the respiratory membrane.

 Alveolar (thin) epithelium.

 Capillary endothelium.

 Fused basement membranes of both epithelial  


Page Expired
It looks like your free minutes have expired! Lucky for you we have all the content you need, just sign up here