Animal physiology

AMOCTOBSO

Atoms
molecules
organelles
cells
tissues
organs
body
system
organism

Ephithelial TIssues

Covers body surfaces, line cavities, and forms glands.
Function: Protection, avbsorption, secretion

Connective tissues

Supports, binds and protects other tissues. Even bones, blood,adipose (fats), and cartilage

Muscle Tissue

• Enables movement. Types are: skeletal, cardiac, and smooth.

Nervous Tissue

Transmits electrical signals, composes of neurons and supporting cells

Integumentary system

• Eneclose/ protect internal structures

• Site of many receptors

Key structures: Hair, skin, nails

Muscular systems

• Enables movement (with skeletal)

• Helps maintain body temperature

Key structures:

smooth, cardiac, and skeletal muscles

Skeletal systen

• Enable movement (with mucular)

• Supports the body

Key structures:

bones, ligaments, tendons

Nervous system

• Detect & processes sensory

• activate bodily responses

Structures:

Brain, spinal cord, nerves

Endocrine system

Secretes horomones
regulate bodily preocesses
Key strucutres:
pituitary gland, thyroid, pancrease, adrenal glands, testes/ ovaries

Uniary/ Renal system

• Control water balance & homeostasis

• remove waste from blood & excretion

key structures:
kidneys, bladder

Immune system

• Protect body aganist pathogens

• filter & return fluids to blood

Key structures:

Lymoh nodes, spleen, thymus

Reproductive systems

• Produce sex horomones & gametes

  • Male = deliver gametes

  • female= support embryo to birth & produce milk for infant

Structures:

Testes, ovaries, uterus, mammary glands

The big 3 systems

Respiratory:

• Removes carbon dioxide from the body

• Delivers oxygen to blood

Circulatory system:

• Delivered oxygen and nutirents to tissues

• Equalizes temperature in the body

Digestive system:

• Processes food for use by the body

• Removes wastes from undigested food

3 parts system for homeostasis

Sensors ditect imbalance, the control center processes information and then produces and responds to restore internal body enviroment

Negative feedback

• Primary method for homeostasis

• The nerve cells in your skin and brain detect heat

• The temperature regulatory center in the brain recieves the signal

• The body triggers sweat glands

Negative = The response that reverses stimulus

Positive feedback

• Amplifies responses to complete the physiological process quickly

Ie.

Baby pushes aganist cervix, streching of cervix causes nerve impulses to be sent to brain. The brain stimulates posterior pituitary to release oxytocin. The oxytocin causes smooth mucle lining of the uterus to contract.

Epiglottis

Cartilaginous flap that blocks food from entering airway when swallowing food

• Its opened when breating and during resting states

• Closes to cover the trachae during swallowing so food or liquid can’t enter the lungs

Larynax (voice box)

• Found direcly belown the epiglottis

• Home of vocal cords which fold and vibrate to producec sound/ speech

Trachea

• Tube lined with cartilage rings to hold it open

• Lined with cillia (which are hair-like cellular extension) that trap and expunge particulates

• Main transport airqay to transport air in and out of the lungs

Lung

• Comprised of multiple spongy lobes

• Right is bigger than the left to accommodate because the heart on the left side.

• The left and right is based on your own perspective

Bronchi & Bronchioli

Branched narrowings of trachea supported by cartilage rings

Terminate at alveoli

Alveoli

• Where the gas exchange happens. Allows for the transprt of oxygen.

• Increases absoptive surface area

• The aveolar wall is 1 cell thick, where blood is on the other side (the capillaries)

Diaphragm

• Responsible for inhale and exhalation

• Controled by the autonomic nervous system

• Relaxed when it’s curved and when flat it’s contracting

Breathing control

Controlled by medulla obolongata in the brain which searches for CO₂ and pH of the blood.

pH and CO₂

Detected by chemosensors in aortic and carotid bodies to prompt change in ventilation rate

• More CO₂ you have in your blood, the more acidic your blood is going to be.

chemosensors

Molecular/cellular sensors that detect change & produce a signal

Non-respiratory systems

1. Sneezing & coughing

   1. Purges airway and obstructions/ irrtiants

2. Hiccups

   1. Spasms of the diaphragm caused by sudden intake of breath

3. Laughing & sobbing

   1. Emotional response influences respitaroy rhythms

4. Yawns

   1. Unknown, might be linked to empathy

Gas exchange: O₂ Journey

1. O₂ dissolved in mucuos

2. Diffuses down into gradient into blood

3. Binds hemoglobin in a RBC & circulates

4. Hemoglobin releases it to tissues that lack O₂

5. O₂ drive cell respiration in the mitochondria

Gas exchange: CO₂ Journey

1. Diffuses into blood & circulates to lungs

2. Diffuses down into gradient into aveoli

3. Exhale

Total lung capcity

Volume of air in the lungs after maximal inhalation

Vital capacity

Volume of air that can be exchanged by the lungs via maximal inhalation and exhalation

Residual volume

Volume of air that is always present in the lungs (20% of total lung capacity)

Tidal volume

Volume of air that is exchanged via normal breathing

Three substems of circulatory system

Pulmonary:

• Move O₂ (Poor blood from heart to lungs and back)

• Oxygenates blood and removes CO₂

Systemic:

• Move O₂ (Rich blood from heart to body and back)

• Deoxygenates blood and collects CO₂

Cardiac:

• Feed O₂ (Rich blood to heart itself)

The heart

Muscular organ that pumps blood through the body

Blood vessels

Tubes that direct blood flow

Blood

Nutrient- rich connective tissue. It enables the transport of substances from the external enviroment to every cell in the body.

Consists of:

• Plasma

• Cells and plateles (fromed elements)

flow of blood

Path way for deoxygenated blood: Heart’s right atrium—> right ventricle—> pulmonary atery —> lungs.

And then, gas exchange

Pathway for oxygenated blood:
Left atrium —> left ventricle —> Aorta —Rest of the body + heart

Atrioventricular Valves

Tricuspid valve: Door between your right atrium and right venticle

Mitral valve: Door between your left atrium and left ventricle

Semilunar valves

Aortic valve: Opens when blood flows out of your left ventricle to your aorta

Pulmonary valve: Opens when blood flows from your right ventricle to your pulmonary artery

Ateries

• Carry blood away from heart

• Thick walls withstand high pressure

Capillaries

• Smallest vessel

• RBC’s travel in single file and slowly

• Body cells are not bigger than 2 cell widths away from a capillary

• Connect veins and ateries

Veins

• Low pressure blood pressure returns to heart

• Semi-lunar valves prevent backflow

• Carries blood from the body cells to the heart. They carry waste.

Plasma

Fluid-suspension of proteins and dissolved nutrients

Erythrocytes (RBC’s)

• Lack nuclei, ribosomes, & mitochondria

• Carries O₂ and CO_2,

Leukocytes (WBC’S)

Cells of the immune system

Thrombocytes (Platelets)

Involved in clogging and not considered a true cell

Differences between Arteries Vs Veins

Flow direct: Arteries flow away from the heart, veins toward

Pulse: Present and the wall strech by pressure, veins have no pulse because they are too far from the heart

Walls: Arteries are thick, muscular, and elastic for blood pressure. Thinner, less muscular & elastic (can be permentantly streched)

Type of blood carried: Artieries, oxy and deoxy. Veins: Deoxy and oxy
Colour: Arteries: bright red and veins are dark red
Dialation & constriction: A: Easily archieved V:Less easily archieved
Valves: A: No V: Yes
Cause of blood flow: A: heart pumping, V: Contraction of skeletal muscles
Flood if served: A: Blood spurts, no clotting (high BP) V: Slow, even flow, and blood clots

The cardiac cycle

Contraction: systole, these are controlled by the heart itself
Relaxation: diastole

Blood pressure

• Measures the force of blood on the walls of arteries

• Measured with a sphygmomanometer

2 pressures measured:
Systolic: Highest, ventricles pushing blood
Diastolic: Lowers, chambers relax and fill with blood

• Measured as systolic/ diastolic in mmHg

• Health is 120/80

Hypertension

Sustained high blood pressure

Risks:

• Organ damages

• Blood vessel damage can cause an anerism (in heart= heart attack, in brain = stroke)

Two different types of strokes:

- Ischaemic: Where the blood is blocked

• Haemorrhagic: A bleeding of an atery

Prevention:

• Good diet

• Medication (diuretics to reduce blood volume)

Aneurism

A weakening of an atery wall that creates a bulge or distention of the atery

Hypotension

Abnormall low bp (90/160)

Risks:

• Light headedness, dizziness, weakness, fainting

• Brain damage

Prevention: hydration

Orthostatic/ Postural hyoptension

Sudden blood pressure drop due to stand up from a lying or sitting position. Common

Circulatory system in animals

• Not all animals have circulatory systems

• Some organisms that are complex have two layers of cell in their body plan, which use diffusion through their skin.

• Both internal & external tissue are in contact with an aqueous enviroment making diffusion an easy task

Close circulatory system

Where blood is entirely contained within vessels. (Arteries, veins and capillaries) and it circulates

Amphibians

• They have three- chambered heart. 2 atria + one ventricle

• Single ventricle: Pumps mixed blood to the lungs, skin , and the rest of the body.

Circulation: Double circulation system

• Pulmonary circulation: Moves bloodbetween the heart and lungs/ lungs for oxygenation Gas exchange happens during circulation: pulmocutaneous circulation

Fish

• Two chambered heart with 1 atrium and 1 ventricle

  • Atrium: Recieves deoxygenated blood from the body

  • Ventricle: Pumps doxygenated blood to the gills for oxygenation

Gill circulation

The atrium cellects blood that returned from the body and ventricle pumps the blood to the gills where gas exchange happens and the blood is reoxygenated

Open circulation

• When blood is not enclosed in blood vessels. The fluid is pumped into a cavity called a hemocoel

• Blood mixes with interstital fluid creating hemolymph which is pushed around the when the heart beats in the body

• Ostia: the opening that allows blood to re-enter the heart after circulation

• common in insects and mollusks

Insects

• open circulation

• Sinuses: Spaves within the hemocoel where hemolyph bathes the organs directly

• Trachea: A network of tubes that provide direct air exchange and reduces the reliance on the circulatory system for oxygen delivery

• Aorta: carries hemolymph from the heart to the body cavity in some anrthopods

Open system: circulatory system

• Snails and clams

• Hemolymph flows into hemocoel, the simple heart pumps through vessels

Closed system mollusks: cephalopods

Blood stays in veseels and they have a more complex heart system which supports active, high energy life style

Close vs open circulatory systems

• Organs are not in direct contact of blood vs organs come in direct contact with blood

• Blood flow can be regulated and pressure is high vs blood flow cannot be regulated and the pressure is low

• Blood flows through closed spaces and have capillaries vs flows through open spaces and dont have capillaries

• Materials transported by the blood arrives to the tissues through diffusion vs blood pumped by heart travels to the blood vessels and soak directly into cells returing then by different mechanisms

• 1 heart vs 1 or 2

• Oxygenated blood can reach the extremeties of the body much faster vs can support a high activty body by burning less calories to move the same amount of oxygen

• They can metabolize much faster because it lets them move, digest, and eliminate waste quicker vs takes more time to reach the extremeties of the body and is only feasible in smaller animals

Enviromental impact of using insects

• Lower enviromental impact compared traditional livestock

• Require less land, water, and food to grow and emit fewer greenhouse gases

Bugs in products

• Shellac: Shiny coating on candies and apples, made from resin secreted by lac bugs

• Carmine: red pigment from cochinal insects, used in foods like strawberry yogurt, candy, and cosmetics

• Cricket flour: Sustainable and protein-rich flour in proteins bars, baked goods, and pasta.

Functions of the digestive system

Primary: Breaks down large molecule into smaller molecules for absorption
Secondary: Hold mutualistic bacteria that aid in digestion and waste excertion

Enzymes

Biological cataslysts that allows most chemical reaction carried out in a cells

• Not change or used up

• Bond molecules together to form new molecules or molecules apart

3 main enzymes

Amylase, Lipase, Protease

What are the enzymes that break carbohydrate down to glucose

• Amylase

• Sucrase-Isomaltase

• Maltase,

• lactase

Protein to Amino Acids

Enzymes used: Pepsin, Trypsin, Petidase breakdown into amino acids

Fatts to fatty acids/ Glycerol

Lipase breaking fats downing int fatty acids and Glycerol

Gastrointestial tract vs digestive system

• Specific part of the digestive system. Its the continuous tube that runs mouth to BUTTHOLE

• Digestive system: All organs involved in the process of digestion

Ingestion

• Food ingested through the broke down through mastication

Main functions:

• Ingests food

• Bolus: Chews and mixes

• Used amylase to breakdown of carbohydrates

Swallowing:

• Tongue and plate press food into bolus

• Tongue and throat muscles and guide bolus over to epiglottis into esophagus

• Peristalsis pushes bolus to the stomach

Endoscopy

Internal observation of the upper digestive system

Colonoscopy

Internal observation of the large intestine

Sphincter and Ingestions

Sphincter: Circular muscles that controls movement through the body

• Food passes through 2 sphincters on the way to the stomach

  • Upper esophageal sphincter (barrier to air)

  • Lower esophageal sphincter (barrier to acid)

Taste buds + Salivary Glands

Slivary glands:

• Moistens and dissolves, allowing for swalling

• contains carbs

Taste buds: Detecting nutrients in food we eat that trigger hormonal responses to regulate digestion, absorption, and appetite control

Mechanical digestion

The physical breakdown of food to high surface for chemical digestions. First in the mouth

Chemical digestion

Breaking down of nutrients into absorbable molecules (mostly via enzymes)

• Happens in the mouth —> stomach —> small interstine

Digestion in the stomach

Main functions:

1. Store swallowed food and liquid

2. Chrun the food, liquid, and digestive juices produced by the stomach

3. Slowly empty its contents into the small intestine

• Only a few substances such as water, aspirin, and alcohol can be abosrbed into blood directly from the wall of the stomach

• Main enzymes: protease + lipase

Gastic Glands

Consists of:

• Muscous cells that secrete alkain mucus to protect lining of the stomach

• Chief cells

• Parietial cells: Secretes HCL

Absorption in small intestine

• Responsible for absorbing majority of nutrients into (bloodstream)

• 6m long, holds some bacteria that help in digestion

• Big SA to boost absorption

  • SA is maximized by Villi and microvili

Villi

Finger-like projection on inner surface of small intestine

Microvilli

Hair-like projection of surface of villi. Absorption direct nutrients into bloodstream

Absoprtion in large intestine

• From small intestine, chyme is a water, salty waste product

• The ileocecal sphincter opens and allows the product to the large intestine

• Waste is called stool or feces

• Will absorb water and minerals, causes feces to solidify and clump

Microbiota of the large intestine

• Harvesting energy from digested

• Protecting aganist pathogens

• Regulating immune function

Gut dybosis

When there is an imbalance of benefical bacteria in the gut

• Infections: Chlostridium difficile, Crohn’s disease, and infalmmatory bowel disease

Elimination

• Process of removing undigested food and waste products from the body

• Rectume: Short length of the colon where feces for defaction

• When the rectal wall streches, triggers the urge to eliminate feces from the body

• Acieved by allowing/pushing feces through the anal sphincter (anus)

Birds digestive systems

• Birds can eat a variety of foods (insects, worms, berries, seeds, etc.)

• The crop stores food

• Most chemical digestion occurs in the stomach

The gizzard is filled with gravel/pebbles the bird eats to mechanically digest food stuffs

Gastroesophageal Relux Disease

• Occurs when the lower esophageal sphincter fails to close properly. This allows toach acid to flow backwards into the esophagus

• Frequent exspoure to acid causes inflammation known as esophagitis and can to barrets esophagus (precancerous change in the tissues cell type)

Peptic Ulcers

• Erosion of the lining

• Caused by H. pylori bacteria and longer term pain medication use. Which depeletes the protective layer

Celiac Disease

• An autoimmune disorder where the ingestion of gluten that propts the immune system to attack the small intestine

Nutient Malabsorption

Immune response that damages and flattens the villi.

• The finger-like projections responsible for nutrient absorption which leads to malnutrition no matter how much food is consumed

Appendicitis

• Inflammation of the appendix due to bacterial infection

• Can ruprure if not removed

IBS

• Causes cramping, abdominal pain, bloating, gas, diarhea/ constimation

• No known cause

• Treatment: Managed diet

Colon cancer

• Cancer of the large intestin

• Detected when there is blood in your stool

• Treatment: Surgical removal of section and chemotheraphy

Colostomy bag

• stoma is formed in abdominal wall that provides alternate exit for colon

• FEcal matter is collected in a replaceable bad instead of passing through

Gallstones

• Chloesterol or bilirubin in the bile hardens into stone-like deposits

• The stones block the common bile duct, preventing bile from entering the duodenum. Needs to be removed with laproscopic surgery