Human Excretion

Question 1

What is excretion ?

Answer 1

The removal of metabolic waste

Question 2

What does the Kidney do?

Answer 2

• Balances the amount of water in your body - osmoregulation
• Filters urea
• Removes excess water, salts and urea

Question 3

As the blood is filtered at high pressure…..

Answer 3

The kidney selectively reabsorbs any useful materials (glucose, salt ions and water)

Question 4

What does the kidney produce ?

Answer 4

Urine

Which contains water, urea and salts

Question 5

How is urea produced?

Answer 5

Urea is produced in the liver when excess amino acids are broken down

Question 6

What are the excretory organs?

Answer 6

Lungs, kidneys and skin

Question 7

Excess CO2 is removed through the…..

Answer 7

Lungs

Question 8

Excess urea, water and salts are removed by….

Answer 8

The kidneys and leave the body as urine

Question 9

Excess water and salts leave the body through….

Answer 9

Skin through sweat

Question 10

How do the kidneys regulate the osmotic pressure

Answer 10

Extensive filtration and purification - osmoregulation

Question 11

Kidneys remove the the blood….

Answer 11

The nitrogenous wastes and then excrete them in the form of urine

Question 12

How is the filtrate blood carried away from the kidneys

Answer 12

By the renal vein

Question 13

What does the urinary system consist of?

Answer 13

Kidneys, ureters, bladder and urethra

Question 14

How does the urinary system work?

Answer 14

1) kidneys filter blood to remove unwanted substances
2) ureters move urine from kidneys to bladder
3) bladder is a reservoir for urine
4) urine excreted through urethra

Question 15

What a nephron responsible for?

Answer 15

Cleaning the blood

Question 16

In a nephron at the start is blood at high or low pressure?

Answer 16

High

Question 17

How does the structure of the blood vessels entering and leaving the glomerulus help to move glucose into the Bowman’s capsule?

Answer 17

The after went arteriolar is significantly wider than the efferent arteriole
Pressure increase in the Bowman’s capsule

Question 18

What type of blood vessels are found in the glomerulus

Answer 18

Capillaries

Question 19

What does high pressure help

Answer 19

The ultrafiltration of the blood

Question 20

What does small molecules do in a nephron?

Answer 20

They are filtered out and pass into the nephron

Question 21

What do large molecules do in the nephron

Answer 21

They are too big to fit through the capillary wall, remain in blood

Question 22

What molecules are selectively reabsorbed into the bloodstream?

Answer 22

All glucose originally filtered out
Water required to maintain a constant water level
Ions

Question 23

What happens to the molecules which are not selectively reabsorbed ?

Answer 23

They continue along the nephron tubule as urine

Question 24

What happens in the loop of Henle?

Answer 24

More water, sodium ions out (by diffusion and AT)

Question 25

Why does selective reabsorbtion occur?

Answer 25

Because during ultrafiltration, important components of the blood is filtered out and need to be reabsorbed into the body

Question 26

Where does selective reabsorption occur?

Answer 26

In the proximal convoluted tubule (extends from Bowman’s capsule)

Question 27

How is the proximal convoluted tubule adapted for selective reabsorption?

Answer 27

Has a microvilli cell lining to increase surface area One cell thick Mitochondria

Question 28

What is ultrafiltration ?

Answer 28

The filtration of particles / molecules based on their size and under pressure

Question 29

What is the name of the target cells that line the collecting duct?

Answer 29

Epithelial cells

Question 30

What happens when receptor molecules bind to the ADH

Answer 30

It triggers proteins in the cell membrane to form pores that allow water to move freely out of the collecting duct by osmosis Increase water reabsorption Decrease blood concentration

Question 31

What does ADH do?

Answer 31

Tells your kidneys how much water to conserve

Question 32

Explain the role of ADH in regulating the water content of the blood

Answer 32

1) hypothalamus detects solute concentration of blood 2) if water concentration is low, pituitary gland secreted ADH 3) ADH travels in plasma of blood 4) Makes collecting ducts more permeable today water ( allows more water to be reabsorbed back into blood during selective reabsorption)

Question 33

What does FSH help with

Answer 33

Pubertal development | Function of women’s ovaries and mend testes

Question 34

What does the ride of LH trigger

Answer 34

Ovulation