Week 13: Interdependence Osmoregulation Control Of Blood Pressure

Question 1

What is osmosis?

Answer 1

The diffusion of water across a membrane in response to osmotic pressure caused by an imbalance of molecules on either side of the membrane

Question 2

What’s osmoregulation?

Answer 2

The process of maintaining salt and water balance (osmotic balance) across membranes within the body’s fluids

Question 3

Why are osmoregulation and osmotic balance important?

Answer 3

Without these, toxic waste and water can accumulate in the body.

Question 4

What is osmolarity and the units used?

Answer 4

Total number of particles in a solution (Osmoles/L)

Question 5

What is molarity and the units used?

Answer 5

Number of particles of a solute in a given volume of solvent (Moles/L)

Question 6

What is osmolality and the units used?

Answer 6

Total numer of particles in a given mass of solvent (Osmoles/kg)

Question 7

What is molality and the units used?

Answer 7

Number of particles of a solute in a given mass of solvent (Moles/kg)

Question 8

What’s the afferent arteriole? Does it contain blood or filtrate?

Answer 8

The capillary network that supplies the nephron with blood to be filtered (Enters glomerulus)

Has blood

Question 9

What’s the Bowmans’ capsule or glomerular capsule? Does it contain blood or filtrate?

Answer 9

A capsule-shaped membranous structure surrounding the glomerulus of each nephron

Extracts wastes, excess salts, and water from the blood

Has blood

Question 10

What’s the collecting duct? Does it contain blood or filtrate?

Answer 10

Collects filtrate coming from the nephrons

Has filtrate

Question 11

What’s the distal convoluted tubule? Does it contain blood or filtrate?

Answer 11

The last part of the nephron that connects and empties its contents into collecting ducts

Has filtrate

Question 12

What’s the efferent arteriole? Does it contain blood or filtrate?

Answer 12

The capillary network that supplies the nephron with blood that needs to be filtered (Exits glomerulus)

Has blood

Question 13

What’s the glomerulus? Does it contain blood or filtrate?

Answer 13

The network of capillaries that makes up the renal corpuscle

Has blood

Question 14

What’s the loop on henle? Does it contain blood or filtrate?

Answer 14

The looop between the descending and ascending limbs that goes through the renal medulla

Has filtrate

Question 15

What’s the peritubular capillaries? Does it contain blood or filtrate?

Answer 15

Formed when the efferent arteriole exists the glomerulus
Surrounds the renal tubule

Has blood

Question 16

What’s the proximal convoluted tubule? Does it contain blood or filtrate?

Answer 16

The first part of the renal tubule; close to glomerulus

Has filtrate

Question 17

What’s the vasa recta? Does it contain blood or filtrate?

Answer 17

Where the peritubular capillary network forms a network around the loop of henle

Has blood

Question 18

Describe glomeruluar filtration.

Answer 18

All solutes (except for proteins) are filtered out into the glomerulus using the capillary network. They pass via passive diffusion.

Question 19

Describe secretion.

Answer 19

Solutes and waste enter kidney tubules via active or secondary active transport

Question 20

Describe reabsorption.

Answer 20

Involves most parts of the nephron via passive or active transport

Almost all nutrients are reabsorbed. Water and some key nutrients are regulated.

Question 21

What are osmoconformers? Give some examples.

Answer 21

They do not regulate their body fluid osmolarity; it matches the environmental osmolarity.

Ex. Sponges, some marine invertebrates

Question 22

What are osmoregulators? Give some examples.

Answer 22

They do regulate their body fluid osmolarity.

Ex. Birds, fish

Question 23

What are ionoregulators? Give some examples.

Answer 23

They regulate the concentration of at least some ions.

Ex. Sharks, amphibians, birds, mammals, arthropods

Question 24

What are ionoconformers? Give some examples.

Answer 24

They don’t regulate the concentration of ions.

Ex. Sponges, some marine invertebrates

Question 25

What are euryhalines? Give some examples.

Answer 25

They tolerate a wide environmental osmolarity range.

Ex. Octopus

Question 26

What are stenohalines? Give some examples.

Answer 26

They tolerate a narrow environmental osmolarity range.

Ex. Eel

Question 27

Describe the osmoregulatory mechanisms of freshwater fish.

Answer 27

They drink little water, passively absorb water through their skin, actively take up ions through their gills, and excrete dilute urine.

Question 28

Describe the osmoregulatory mechanisms of saltwater fish.

Answer 28

They drink lots of water, passively lose water through their skin, excrete ions through their gills, and excrete concentrated urine.

Question 29

How do contractile vacuoles help regulate osmolarity?

Answer 29

They use endocytosis to allow nutrients and water to move into the cell.

Question 30

How does nephridia help regulate osmolarity?

Answer 30

It’s coated with cilia and helps get water into the pores.

Question 31

How do malphigian tubules help regulate osmolarity?

Answer 31

It’s lined with microvilli and aids with reabsorption.

Question 32

What occurs in the baroreceptor system when blood pressure increases? Decreases?

Answer 32

When blood pressure increases, the baroreceptors are stretched more tightly, initiating action potentials at a higher rate.

When blood pressure decreases, the degree of stretch is lower, so the firing rate is slower.