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):
1

Osmoregulation

regulation of water and solute balance of tissues and organs

2

excretion

removal of metabolic rates
-include CO2
-nitrogenous wastes produced as a result of deamiations of amino acids and nucleotide breakdown

3

water distributed between?

intracellular compartment
-extracellular compartment-tissue fluids

4

Important ions in osmolarity

sodium is the major cation in extracellular fluids
-chloride is major anion

5

Osmotic pressure

force of water moving into cell by osmosis
-measure of a solutions tendency to take in water by osmosis

6

tonicity

solute concentration of a solution
-solutions may be hypertonic, hypotonic, or isotonic

7

osmoconformers

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

8

Osmoregulators

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

9

Freshwater vertebrates with osmolarity

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

10

Marine vertebrates and osmolarity

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

11

terrestrial vertebrates and osmolarity

-higher concentration of water than surrounding air
-tend to lose water by evaporation from skin and lungs

12

osmoregulatory organs in flatworms

use protonephridia which branch into bulblike flame cells

13

Earthworms

-use nephridia
-open both to the inside and outside of the body

14

Insects

-use mapighian tubules

15

Vertebrate kidneys

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

nitrogenous wastes

made up of amino acids and nucleic acids
-first step is deamination
-combined with H+ to form ammonia

17

Urea

ammonia and other solutes that are released through urine

18

uric acid

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

19

Which organisms directly eliminate ammonia

fish through their gills

20

mammalian excretory system consists of

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

21

where does the kidney get blood from

-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

where does urine go from kidneys

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

where are the nephrons located

inner renal memdulla

24

nephrons consist of what?

glomerulus and tubular system

25

kidney is made up of what?

1 million function nephrons

26

steps of blood filtration

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

3 basic kidney functions

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

where is water reabsorbed in the kidneys

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

29

what else do the kidneys reabsorb besides water

glucose and amino acids through active transport

30

proximal convoluted tubule

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

31

loop of henle

-creates a gradient of increasing osmolarity from the ocortex of the medulla
-allows reabsorption of water from descending loop and collecting duct

32

ADH

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

aldosterone

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

ANH

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