Homeostasis Flashcards

Question

Ammonia What uses this form of nitrogenous waste? Qualities?

Answer 1

Aquatic animals Highly soluble, toxic, quickly flushed if enough water is available 500 mL water to 1g of nitrogen waste Fish are not concerned with water conservation mostly

Answer 2

Amphibians, mammals Fairly simple compound, relatively nontoxic, soluble 50 mL water to 1g of Nitrogen waste Requires energy to convert ammonia to urea (15% of energy gained by amino acids is spent doing this)

Answer 3

Urea excreting in urine

Answer 4

Birds, insects, reptiles More complex than urea More energetically expensive to produce than urea highly insoluble in water <10 mL of water per 1 gram of Nitrogen wasteW

Answer 5

Keeps body-weight low and conserves water

Answer 6

Ammonia is a small enough molecule to diffuse out of the body via respiratory membranes or body surfaces

Answer 7

Bowman's capsule -> p conv tubule -> loop of henle -> distal conv tubule -> collecting duct -> renal pelvis -> ureter

Answer 8

Glomerulus and bowman's capsule

Answer 9

Cortex is outer, Medulla is inner

Answer 10

Water, Urea, Excess ions

Answer 11

20-25 200 liters of blood

Answer 12

Aorta -> renal artery -> afferent arteriole -> glomerulus -> efferent arteriole -> renal vein -> inferior vena cava

Answer 13

Glomerular filtration tubular reabsorption tubular secretion water excretion/concentration of urine

Answer 14

Occurs due to hydrostatic pressure in the glomerulus Filtration slits allow water and small ions to leave Produces protein-free filtrate Non-selective (200L is formed daily)

Answer 15

Reclamation of valuable materials from the filtrate to peritubular capillaries Primarily occurs in the prox conv tubule ~60% glucose, amino acids, vitamins Active transport (unique ion pumps gather ions) Water passively follows the osmotic gradient with active reabsorption of solutes

Answer 16

-Nephron secretes materials into the filtrate (reverse of tubular reabsorption) -Occurs in dist conv tubule -Active transport of hydrogen ions, potassium ions, and drugs In the urine

Answer 17

Kidney closely regulates the solute concentration of the blood

Answer 18

high - dilute urine low - conc urine

Answer 19

Loop of henle Descending is permeable to water, not NaCl Ascending is permeable to salt, not NaCl Variably permeable to water depending on ADH; permeable to urea

Answer 20

Cortex is low osmolarity Medulla gets extremely concentrated osmolarity as it gets lower towards the descending loop of henle

Answer 21

Increasing solute concentration Decreasing water concentration (decreasing solvent concentration)

Answer 22

upper portion, via active transport lower portion, via diffusion

Answer 23

Urine becomes more concentrated Dilute Increases solute concentration of interstitial fluid

Answer 24

increases permeability of collecting ducts to water, causing water retention

Answer 25

Metabolic water vs. Drinking Evaporation (lungs and skin) vs. Urine

Answer 26

They evolve from freshwater fishes, who have a body salinity of 180 mM

Answer 27

Amino acid metabolism. It is important to get rid of nitrogenous wastes because buildup in the body can cause toxicity.

Answer 28

Spider crab dies because it is stenohaline Blue crab (550 mM in brackish) - (passive salt loss, water gain) Green glands move water out, Salt-secreting glands take salt in from the environment Modern freshwater bony fish - (passive salt loss, water gain) Dilute urine, Eating foods with salts, Salt-absorbing cells move salts in Marine bony fish - (passive salt gain, water loss) Drink seawater and retain the water while excreting the salt, Concentrated urine Desert lizard on land - (water loss to evaporation, urine excretion, feces excretion) - Absorb water vapor, concentrated uric acid, retain water well from metabolism

Answer 29

Some animals can afford to spend more water and have a more soluble option in their excretion pathway rather than having a very insoluble uric acid that costs a lot of energy to generate. Also, birds need to be lightweight so they need to minimize water loss. Uric acid is a great way to minimize water loss, so if that is a survival characteristic, then it would be necessary; however, that is not always the case.

Answer 30

Homeostasis - the tendency to remain stable internally in the face of external fluctuations Osmoregulation - the maintenance of constant osmotic pressure in the fluids of an organism by the control of water and salt concentrations Osmoregulation is a system of regulating salt and water balance that maintains homeostatic conditions, thus maintaining homeostasis. Stenohaline - Able to survive in a narrow range of salinities Osmoconformer - The ability to maintain an osmolarity internally that is in sync with the environment These are both describing the ability to survive in an environment which requires relative osmolarities to be a key factor in survival. One is an inability to regulate osmolarity to the point where it cannot survive big changes, whereas the other is describing the ability to conform its internal environment to mimic that of the external environment. Euryhaline - Euryhaline is the ability to survive a cross a wide range of salinities Hyperosmotic regulator - The ability to maintain a high internal osmolarity in a low osmolarity environment These are both describing the ability to survive in an environment which requires relative osmolarities to be a key factor in survival, and both of these characteristics are describing an ability to survive in waters where external environments are different relative to one's internal environment. For example, euryhaline could survive a significant change in its external environment and still survive since it can survive in a wide range of salinities. Hyperosmotic regulators work to survive in an external environment that is different from its own internal environment constantly.

Answer 31

Filtrate is reabsorbed and concentrated with wastes in the nephron. In the proximal convoluted tubule, vital nutrients are reabsorbed along with a lot of water passively going down its concentration gradient with the actively transporting ions/molecules. Water is reabsorbed in the descending loop of Henle down its concentration gradient. Water is also reabsorbed in the collecting duct when ADH is present.

Answer 32

Distal convoluted tubule - tubular reabsorption - where 60% of filtrate is reabsorbed Loop of henle - Water is reabsorbed as well as NaCl Proximal convoluted tubule - tubular secretion occurs here where waste products are placed in the filtrate from the interstitial fluid (protein-free) Glomerulus - Where a big blood vessel meets a little blood vessel, causing hydrostatic pressure to shoot filtrate into the bowman's capsule Bowman's capsule - allows a place for filtrate to be collected, as it is being released from the glomerulus Together, the glomerulus and Bowman's capsule create the renal corpuscle

Answer 33

Tubular reabsorption is the reabsorption of water, amino acids, and sugar from the filtrate, and it is done in the proximal convoluted tubule via active transport. This process is important because reclamation of important materials from the filtrate enables us to actively filter out waste products more effectively and not waste valuable nutrients.

Answer 34

Tubular secretion is important because this is an opportunity for the filtrate to be concentrated with waste products from the body. Without this process, H+, K+, and drugs would not be incorporated in this step.

Answer 35

Desert animals have longer loops of henle to limit the amount of water and salt that they lose, so its increased length allows the loop of henle to extend deeper into the medulla, where more water and salt can be pulled out of the filtrate.

Answer 36

Alcohol inhibits ADH, thus not allowing it to act on the collecting duct and make it permeable to water. As a result, water loss is more extreme while it is inhibited and dehydration is exacerbated.

Homeostasis Flashcards

(61 cards)