Homeostasis - kidney + adaptions.

Question 1

What organ produces nitrogenous waste products?

Answer 1

The liver.

Question 2

Why does the liver produce nitrogenous waste products?

Answer 2

To remove excess nitrogen from the body.

Question 3

Where are nitrogenous waste products transported after production?

Answer 3

To the kidneys for removal.

Question 4

What are the three main nitrogenous waste products?

Answer 4

Ammonia, urea, and uric acid.

Question 5

Rank ammonia, urea, and uric acid in order of energy required to produce.

Answer 5

Ammonia (low) → Urea (medium) → Uric acid (high).

Question 6

Rank ammonia, urea, and uric acid in order of toxicity.

Answer 6

Ammonia (high) → Urea (medium) → Uric acid (low).

Question 7

Rank ammonia, urea, and uric acid in order of water solubility.

Answer 7

Ammonia (high) → Urea (medium) → Uric acid (low).

Question 8

What trade-off must animals make in producing nitrogenous waste?

Answer 8

Between energy conservation and water conservation.

Question 9

Why do freshwater fish excrete ammonia?

Answer 9

Because it’s low-energy to produce and they have access to abundant water.

Question 10

Why do mammals excrete urea?

Answer 10

It has moderate toxicity and requires some energy and water to excrete.

Question 11

Why do birds and reptiles excrete uric acid?

Answer 11

It is non-toxic, conserves water, and can be stored with little water despite high energy cost.

Question 12

What is a structural adaptation?

Answer 12

A physical feature of the organism, such as size, shape, or colour.

Question 13

Give a structural adaptation example related to water conservation.

Answer 13

A longer loop of Henle in desert animals.

Question 14

What is a behavioural adaptation?

Answer 14

An action or behaviour that helps the animal respond to its environment.

Question 15

Give a behavioural adaptation example for saving water.

Answer 15

Nocturnal or burrowing behaviour to avoid heat and reduce water loss.

Question 16

What is a physiological adaptation?

Answer 16

An internal body process or reaction.

Question 17

Give a physiological adaptation example for saving water.

Answer 17

Producing uric acid as a nitrogenous waste product.

Question 18

What is metabolic water?

Answer 18

Water produced internally during cellular respiration.

Question 19

What is the chemical word equation for cellular respiration?

Answer 19

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O

Question 20

What is transpiration?

Answer 20

The evaporation of water from leaves.

Question 21

What causes root pressure?

Answer 21

Water entering roots due to a concentration gradient (more solutes in root cells than in soil).

Question 22

What is the role of root pressure?

Answer 22

It creates an upward force that helps move water up through the plant.

Question 23

What is the xylem?

Answer 23

A continuous water-transport tube in plants.

Question 24

What strengthens the xylem?

Answer 24

Spirals of lignin.

Question 25

What property of water helps with upward movement in xylem?

Answer 25

Cohesion – water molecules stick to each other.

Question 26

What is cohesion in plant water transport?

Answer 26

The attraction between water molecules, allowing them to pull each other upward.

Question 27

What happens when water evaporates from stomates?

Answer 27

It creates negative pressure, pulling other water molecules upward (transpiration pull).

Question 28

What is the transpiration stream?

Answer 28

The continuous movement of water up the plant due to transpiration and cohesion.

Question 29

Is the transpiration stream active or passive?

Answer 29

Passive – it does not require energy.

Question 30

What is adhesion in plant water transport?

Answer 30

The attraction between water molecules and the walls of the xylem – helps resist gravity.

Question 31

What are the 6 components of the nephron.

Answer 31

- Glomerulus - Bowman's capsule - Proximal convoluted tube - Loop of Henle - Distal convoluted tube - Collecting Duct.

Question 32

What is the function of the afferent arteriole in the nephron?

Answer 32

It brings blood into the nephron and has a wide diameter to create high pressure.

Question 33

Why is pressure high in the glomerulus?

Answer 33

Because the afferent arteriole is wider than the efferent arteriole, increasing pressure.

Question 34

What is the process that occurs in the glomerulus?

Answer 34

Pressure filtration (also known as ultrafiltration).

Question 35

What is forced out of the blood during pressure filtration in the glomerulus?

Answer 35

Water, glucose, urea, salts, and amino acids.

Question 36

What substances are too large to be filtered out in the glomerulus?

Answer 36

Blood cells and large proteins.

Question 37

What is the role of the Bowman's capsule?

Answer 37

To collect the filtrate from the glomerulus.

Question 38

What does the filtrate collected by the Bowman's capsule contain?

Answer 38

Water, glucose, urea, salts, and amino acids.

Question 39

What process happens in the proximal convoluted tubule (PCT)?

Answer 39

Selective reabsorption.

Question 40

What is reabsorbed in the PCT?

Answer 40

Most water, all glucose, amino acids, and some salts.

Question 41

How does reabsorption happen in the PCT?

Answer 41

Through active and passive transport.

Question 42

What is the main function of the loop of Henle?

Answer 42

To create a concentration gradient in the kidney medulla.

Question 43

What happens in the descending limb of the loop of Henle?

Answer 43

Water is reabsorbed as the limb is permeable to water.

Question 44

What happens in the ascending limb of the loop of Henle?

Answer 44

Salts are actively pumped out; it is impermeable to water.

Question 45

Why is the loop of Henle important for desert animals?

Answer 45

A longer loop helps concentrate urine and conserve water.

Question 46

What is the role of the distal convoluted tubule (DCT)?

Answer 46

Fine-tunes salt and pH balance; some secretion of waste/drugs. - Active secretion of toxins, ions and urea.

Question 47

What happens in the collecting duct?

Answer 47

Final water reabsorption occurs based on hydration levels.

Question 48

What hormone regulates water reabsorption in the collecting duct?

Answer 48

ADH (Antidiuretic Hormone).

Question 49

What does ADH do in the collecting duct?

Answer 49

Increases permeability so more water is reabsorbed.

Question 50

What is the final destination of urine after leaving the nephron?

Answer 50

Renal pelvis → ureter → bladder.

Question 51

What is the overall function of the nephron?

Answer 51

To filter blood, reabsorb useful substances, and produce urine.