Chapter 51-Osmotic Regulation and the Urinary System Flashcards Preview

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Flashcards in Chapter 51-Osmotic Regulation and the Urinary System Deck (34)
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1
Q

Osmoregulation

A

regulation of water and solute balance of tissues and organs

2
Q

excretion

A

removal of metabolic rates

  • include CO2
  • nitrogenous wastes produced as a result of deamiations of amino acids and nucleotide breakdown
3
Q

water distributed between?

A

intracellular compartment

-extracellular compartment-tissue fluids

4
Q

Important ions in osmolarity

A

sodium is the major cation in extracellular fluids

-chloride is major anion

5
Q

Osmotic pressure

A

force of water moving into cell by osmosis

-measure of a solutions tendency to take in water by osmosis

6
Q

tonicity

A

solute concentration of a solution

-solutions may be hypertonic, hypotonic, or isotonic

7
Q

osmoconformers

A
  • organisms that are in osmotic equilibrium with their environment (adjust tonicity to match their environment)
  • only hagfish, sharks and relatives are isotonic
8
Q

Osmoregulators

A

majority of organisms

-maintain a relatively constant blood osmolarity despite different concentrations in their environment

9
Q

Freshwater vertebrates with osmolarity

A

hypertonic to environment

-adapted to prevent water from entering their bodies and to actively transport ions back into their bodies

10
Q

Marine vertebrates and osmolarity

A

hypotonic to their environment

-adapted to retain water by drinking seawater and eliminating the exess ions through kidneys and gills

11
Q

terrestrial vertebrates and osmolarity

A
  • higher concentration of water than surrounding air

- tend to lose water by evaporation from skin and lungs

12
Q

osmoregulatory organs in flatworms

A

use protonephridia which branch into bulblike flame cells

13
Q

Earthworms

A
  • use nephridia

- open both to the inside and outside of the body

14
Q

Insects

A

-use mapighian tubules

15
Q

Vertebrate kidneys

A

create a tubular fluid by filtering the blood under pressure through the glomerulus

  • most of the water and molecules are reabsorbed into the blood
  • waste products are eliminated from the body in the form of urine
16
Q

nitrogenous wastes

A

made up of amino acids and nucleic acids

  • first step is deamination
  • combined with H+ to form ammonia
17
Q

Urea

A

ammonia and other solutes that are released through urine

18
Q

uric acid

A

only in mammals, from degradation of purines, not amino acids

19
Q

Which organisms directly eliminate ammonia

A

fish through their gills

20
Q

mammalian excretory system consists of

A
  • 2 kidneys-filters blood; forms urine
  • 2 ureters-connects kidneys to bladder
  • 1 bladder-urine storage system
  • 1 urethra-exit from body
21
Q

where does the kidney get blood from

A
  • each kidney receives blood from a renal artery
  • blood flows to kidneys over and over again and is filtered many times per day
  • kidney produces during from this blood
22
Q

where does urine go from kidneys

A

drains from each kidney through a ureter into a urinary bladder for temporary storage
-urine is passed out of body through urethra by urination

23
Q

where are the nephrons located

A

inner renal memdulla

24
Q

nephrons consist of what?

A

glomerulus and tubular system

25
Q

kidney is made up of what?

A

1 million function nephrons

26
Q

steps of blood filtration

A

carried by an afferent artiole to the glomerulus

  • filtered as it is forced through porous capillary walls of the glomerulus into the bowmans capsule to for the renal filtrate
  • goes into proximal convoluted tubule
  • moves down medulla and back up into cortex of loop of henle
  • leaves henle, fluid is delivered to distal convoluted tubule in cortex
  • drains into collecting duct
  • merges w/other collecting ducts, emptys urine into pelvis
27
Q

3 basic kidney functions

A
  1. filtration-between glomerulus and bowmans capsul (non selective)
  2. reabsorption-mostly proximal tubule
    - selective movement of certain solutes out of the filtrate back into the blood via peritubular capillaries
  3. secretion-mostly distal tubule
    - selective movement of substances from the blood into the extracellular fluid, then into the filtrate in the tubular system
28
Q

where is water reabsorbed in the kidneys

A

proximal convoluted tubule, descending loop of Henle, and collecting duct

29
Q

what else do the kidneys reabsorb besides water

A

glucose and amino acids through active transport

30
Q

proximal convoluted tubule

A

actively, selectively, reabsorbs virtually all nutrient molecules in the filtrate, and two thrids of the NaCl and water

31
Q

loop of henle

A
  • creates a gradient of increasing osmolarity from the ocortex of the medulla
  • allows reabsorption of water from descending loop and collecting duct
32
Q

ADH

A

antidiuretic hormone

  • produced by the hypothalamus and secreted by the posterior pituitary gland
  • stiumulated by an increase in the osmolarity of blood (dehydration)
  • more ADH increases reabsorption of water
33
Q

aldosterone

A

secreted by adrenal cortex

  • stimulated by low levels of Na+ in blood
  • causes reabsorption of of na+
  • low levels of Na+ in blood are accompanied by a decrease in blood volume
34
Q

ANH

A

atrial natriuretic hormone

  • opposes the action of aldosterone in promoting salt and water retention
  • promotes the excretion of salt and water in the urine and lowering blood volume