1. Introduction to Animal Physiology
Chapter 20

2. Just like in plants

3. Let’s take each of these one at a time.

9. What type of tissue is composed of cells embedded in a matrix
What type of tissue is composed of cells embedded in a matrix? a) nervous b) epithelial c) muscle d) connective e) None of the above are correct.

10. Which of the following is a main benefit of multicellularity?
a) Each cell can perform all of the necessary physiological processes needed by the body.
b) Each cell can dump its waste directly into the environment.
c) Only some body cells need to make ATP. 
d) Cells can divide up the labor of performing essential physiological processes.
e) Each cell has direct access to nutrients in the environment.

11. Body Organization
Different types of tissues working together for a common function = organ
Different organs working together for a common function = organ system

12. Organ Systems Overview

20. Which organ system(s) control or regulate body activities?
a) nervous system b) endocrine system c) circulatory system d) immune system e) Both a) and b) control or regulate body activity.

21. What is the function of the respiratory system?
a) exchange gases between the internal and external environment
b) recycling fluids that leak from the circulatory system
c) transport gases to and from tissues in the body
d) make ATP from glucose and other energy-rich molecules
e) purify the blood by filtering out wastes

22. Homeostasis – Maintaining a stable internal environment

23. Homeostasis varies

24. What are advantages of each?

25. Various methods for maintaining body temperature: physical such as fat insulation, behavior such as body position or nest orientation to max absorbing radiation from sun, physiological such as panting or sweating to gain evaporative cooling, Cellular such as metabolic processes that generate heat and warm body.

26. Excretory System 2 main functions:
Maintains the proper water balance for body
Cleans blood of waste bi-products

27. What is osmosis?
The diffusion of water across a semi-permeable membrane
Why should we care?
Our cells are sacs with semi-permeable membranes
Without the proper balance of water in cells, life systems shut down

28. Osmosis con’t
Water will move from a dilute solution to a concentrated solution
Salt concentration - # water molecules/# salt ions

29. Relative Osmotic Pressure
Demonstrated in the last slide
Concentration of solutions relative to adjoining solutions (one cell to the next cell or body relative to surroundings, etc.)
Ex. Red Blood Cell in different solutions
Which one is in a saltwater solution (hypertonic), saline (isotonic), freshwater (hypotonic)
Cell membrane will allow water to cross membrane freely but not other ions or molecules. A B C

30. Real world problems relative to this issue:
Different environments present different problems
Marine – tendency to gain salt + lose water
Freshwater – opposite – gain water, lose salt
Terrestrial – dry – very hypertonic
Humans drink ml/day
get from metabolism
gain
Urinate ml/day
Lost due to evaporation: 1000 ml/day

31. Solutions to water balance problems:
Physical barriers to water movement
Scales on fish, cuticle, hair, feathers
Pump water or salt from body
Urinate, flame cells of Planaria
Salt glands of marine birds and reptiles
Pump water or salt into body
Drink
Freshwater fish have gill pumps that take in salt and concentrates it in the blood

32. 2nd Function: Waste Removal
Waste – what is it?
Ammonia (NH3) is the most toxic
Biproduct of protein breakdown
If eliminated in its pure form – needs to be with lots of water – ex. Freshwater animals
If terrestrial and need to conserve water –
Ammonia is changed to a less toxic form
Chemical change requires energy
Urea – 2 ammonia + CO2 (fish, amphibians, mammals, some invertebrates)
Uric Acid – ring structure = powdery product (terrestrial organisms in dry locations)

33. Other Wastes: Excess Ions Toxins Excess vitamins
Other unneeded breakdown products
Ions = Na, H, K, Cl, Mg, Ca

34. Systems vary among animals
Single celled animals – contractile vacuoles
Earthworms – tube with cilia filters coelomic fluid and blood vessels associated with tube give off waste from blood

35. Mammals – ex. Human Body has different fluid compartments:
Blood - 5% body wt
Interstitial -15% body wt
(lymph collects and returns to blood)
Intracellular (inside cells of body) – 50% body wt
All accumulates waste and needs to be filtered and cleaned. Cell waste dumped into interstitial, lymph puts that into blood. Blood is filtered and cleaned.

36. Parts of Excretory System
Urethra has a sphincter that allows voluntary control up to a point. Kidney = mj osmoregulatory + excretory organ in mammals.

37. Nephron
1 million/kidney

38. Secrete molecules/ions into nephron
Filter blood
Secrete molecules/ions into nephron
Reabsorb some ions/molecules
Regulate amount of water lost
Eliminate urine
1. Blood pressure high in glomerulus due to control of muscle control of walls of afferent and efferent blood vessels
1/5 of blood plasma is forced into Bowman’s capsule from glomerulus capillaries. All but larges molecules.

39. Secretion (2) Reabsorption (3)
Selective (requires energy) transport of additional molecules in blood into proximal tubule
Reabsorption (3)
Selective (requires energy) transport of needed substances back into blood
Most of water, solutes such as sodium, amino acids and glucose
Proximal tubule

40. Osmoregulation (4) Loop of Henle
Salt gradient in cortex and medulla of kidney
Medulla high conc
Water removed from tubes
Bottom of loop – inside tube = hypertonic
Upward arm of Loop – membrane not permeable to water
Salts pulled out
More water pulled out through wall of collecting duct
Proximal tubule – isotonic; Loop moves down into medulla

41. Distal Tubule (2 +3) Collecting Duct
Drugs and toxins removed from blood
Again much by active transport (requires energy)
Collecting Duct
Eliminates urine (5)
Proximal tubule – isotonic; Loop moves down into medulla

42. What is the correct order of flow through the parts of a nephron?
Bowman’s capsule, proximal tubule, loop of Henle, distal tubule, collecting duct
Loop of Henle, Bowman’s capsule, proximal and distal tubules, collecting duct
Proximal tubule, loop on Henle, distal tubule, collecting duct, Bowman’s capsule

43. High blood pressure needed for whole system to work
High blood pressure needed for whole system to work. If lose blood pressure for any reason, kidneys can fail, body rapidly becomes poisoned by accumulating waste. Also high energy requirements for proper function.HCO3 = bicarbonate.

44. High blood pressure medication can be simply a diuretic
High blood pressure medication can be simply a diuretic. How would this work to lower blood pressure?
Diuretic = makes collecting ducts less permeable to water, so more is lost in urine. What could be the body’s response to a drop in blood pressure? – Vein walls contract – correct volume in heart and arteries.

45. Antidiuretic Hormone (ADH)
Drop in blood pressure detected by heart sensors
Sensor information stimulates hypothalamus to secrete ADH
ADH makes collecting ducts more permeable to water
More water reabsorbed and retained by body, blood volume increases, blood pressure increases
Feedback loop – increased in blood pressure turns off hypothalamus secretion. ETOH inhibits ADH release. Caffine dialates blood vessels, lowers blood pressure, causing ADH secretion and water retention.

46. Animation for Ch 20
7.5 min

47. ________________ gain most of their heat from their environment, while _________________ can use metabolic heat to regulate their body temperature. a) Endotherms; ectotherms b) Plants; animals c) Fungi; animals d) Birds, lizards e) Ectotherms; endotherms

48. Which is the correct order of the processes used by the kidney in forming urine?
a) reabsorption > filtration > excretion b) filtration > reabsorption > excretion c) excretion > filtration > reabsorption d) filtration > excretion > reabsorption e) excretion > reabsorption > filtration
What are the parts of the nephron involved with each process?

49. Read Chapter 21 Circulation & Respiration