Excretion

Question 1

What is excretion?

Answer 1

|s the elimination of metabolic waste from the body

Question 2

What are ectotherms?

Answer 2

They gain or lose heat from or to their external environment

Question 3

What are endotherms?

Answer 3

They generate their own heat from metabolic reactions

Question 4

What does filtration mean?

Answer 4

That water and small molecules pass under high pressure from the blood into the nephron

Question 5

What does reabsorption mean?

Answer 5

That molecules pass from the nephron back into the blood

Question 6

What does active transport mean?

Answer 6

That energy (in the form of ATP) is used to move molecules, often against a concentration gradient (from low concentrations to high concentrations)

Question 7

What does secretion mean?

Answer 7

That some substances pass from the blood into the nephron.

Question 8

What is homeostasis?

Answer 8

Is the maintenance of a constant internal environment in an ogranism.

Question 9

What is skin composed of?

Answer 9

• The epidermis

- The dermis

Question 10

Name the functions of the skin.

Answer 10

• Protection
• Vitamin Production
• Food Store
• Sense Organ
• Excretion
• Temperature Regulation

Question 11

What does the skin do in cold conditions?

Answer 11

• Hairs stand up to keep skin warm
• Blood vessels become narrow to retain heat
• Shivering

Question 12

What does the skin do in warm conditions?

Answer 12

• Sweating, which cools the body due to evaporation

- Blood vessels widen to lose heat

Question 13

What are the main excretory organs?

Answer 13

• Lungs
• Skin
• Kidneys

Question 14

What does the lungs excrete?

Answer 14

Water and carbon dioxide

Question 15

What does the skin excrete?

Answer 15

Water and salts

Question 16

What do the kidneys excrete?

Answer 16

Water, salts and urea

Question 17

What does the urinary system consist of?

Answer 17

Two kidneys, two ureters, the bladder and urethra

Question 18

What does the bladder do?

Answer 18

Stores urine

Question 19

Where is the urine excreted?

Answer 19

Through the urethra

Question 20

What are the functions of the kidneys?

Answer 20

• Excretion of water, salts and urea
• Osmoregulation
• Control of the pH of the blood and body fluids

Question 21

What hormone is involved in controlling the volume of urine?

Answer 21

ADH

Question 22

Where is ADH released from?

Answer 22

The pituitary gland

Question 23

What does ADH cause?

Answer 23

• Increased reabsorption of water in the distal tubule and collecting ducts
• A low volume of urine

Question 24

When is ADH not released?

Answer 24

When we drink sufficient water or consume a low-salt diet.