Excretion, Co-ordination adn responses

Question 1

Where is water reabsorbed in the nephron

Answer 1

Loop of henle and collecting duct

Question 2

Where are salts reabsorbed in the nephron

Answer 2

Loop of Henle

Question 3

Where is glucose reabsorbed in the nephron

Answer 3

Proximal convoluted tubule

Question 4

Function of the cornea

Answer 4

Transparent lens that refracts light as it enters the eye

Question 5

Function of the iris

Answer 5

Controls how much light enters the pupil

Question 6

function of lens

Answer 6

Transparent disc that can change shape to focus light onto the retina

Question 7

function of the retina

Answer 7

Contains light receptor cells - Rods (detect light intensity) and cones (detects colour)

Question 8

Function of the optic nerve

Answer 8

Sensory neuron that carries impulses between the eye and the brain

Question 9

Function of the pupil

Answer 9

Hole that allows light to enter the eye

Question 10

What happens to the eye when the person entered a dark room

Answer 10

• Radial muscles of iris contracted
• Circular muscles of iris relaxed
• Dilated pupil (more light enters eye)

Question 11

Eye change when looking at a near object

Answer 11

-Ciliary muscles contract
-Suspensory ligaments loosen
- Lens shape will be thicker
- Light is refracted strongly

Question 12

Eye change when looking at a distant object

Answer 12

• Ciliary muscles relax
• Suspensory ligaments tighten
• lens shape become thinner
• Light is only refracted slightly

Question 13

What is vasoconstriction and when does it happen

Answer 13

It happens when the person is cold. The arterioles will shrink, therefore it will be further away from the skin. Less heat will be lost and blood flow in skin capillaries will decrease

Question 14

What is vasodilation and when does it happen

Answer 14

It happens when the person is too hot. The arterioles will get wider so more heat will be lost as it is closer to the skin. The blood flow in skin capillaries will increase.

Question 15

where is insulin produced and what is it used for

Answer 15

• Produced in the pancreas
• Controls blood sugar level.

Question 16

where is testosterone produced and what is it used for

Answer 16

• Produced in the male testes
• responsible for the development of secondary sexual characteristics in males

Question 17

What does progesterone do and where is it produced

Answer 17

-Produced in the female ovaries
- Used for maintaining the uterus lining during pregnancy
- It stops the release of FSH andLH which releases the eggs.

Question 18

What does Oestrogen do and where is it produced

Answer 18

-produced by the female ovaries
- Used for the development of secondary sexual characteristics in females and regulating the menstrual cycle
- It causes growth and repair of the lining of the uterus wall

Question 19

How is the ADH used in osmoregulation

Answer 19

Water content of the blood falls below a certain if dehydrated.
More ADH released
collecting ducts more permeable for water to be reabsorbed
Less urine and more concentrated

Question 20

Where is LH and FSH produced and what do they do

Answer 20

They are both released in the pituitary gland
LH: Stimulates the ovary to produce progesterone
FSH: Causes egg to start maturing in the ovary. It also stimulates the ovaries to start releasing oestrogen.