Section 6 - Coordination and Response Flashcards Preview

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Flashcards in Section 6 - Coordination and Response Deck (38)
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2

What is the job of the conjunctiva and what number is it (2)

- Lubricates and protects the surface of the eye

- 1

3

What is the job of the cornea and what number is it (3)

- Cornea refracts light into the eye

- Cornea is transparent and has no blood vessels to supply it with oxygen, so oxygen diffuses in from the outer surface

- 3

4

Explain why a cloudly cornea can cause blindness (2)

- Less light into the eye

- Less light hits retina

5

What is the job of the iris and what number is it (3)

- Controls the diameter of the pupil

- Therefore how much light enters the eye

- 2

6

What is the job of the lens and what number is it (2)

- Focuses the light onto the retina

- 5

7

What is the retina and what number is it (2)

- Light sensitive part covered in light receptors called rods and cones

- 10

8

What is the difference between rods and cones (3)

- Rods are more sensitive in dim light but can't sense colour

- Cones are sensitive to colours but aren't so good in dim light

- Cones are found all over the retina, but there are loads of them at the fovea

9

What is the optic nerve and what number is it (2)

- Carries impulses from the receptors to the brain

- 8

10

What are hormones (2)

- Hormones control things in organs and cells that need constant adjustment

- They are chemicals released directly into the blood

11

What are hormones carried in (1)

- Blood plasma

12

Properties of hormones (3)

- Produced in various glands

- Travel quite slowly

- Tend to have relatively long lasting effects

13

What are the six most important hormones in the body (6)

- ADH

- Adrenaline

- Insulin

- Testosterone

- Progesterone

- Oestrogen

14

Where is ADH produced, what is its role and what are the effects of it (3)

- Pituitary gland

- Controls water content

- Increases permeabilty of the kidney tubules to water

15

Where is adrenaline produced, what is its role and what are the effects of it (3)

- Adrenal glands on top of the kidneys

- Readies the body for a fight or flight response

- Increases heart rate, blood flow to muscles, and blood sugar level

16

Where is insulin produced, what is its role and what are the effects of it (3)

- Pancreas

- Helps control the blood sugar level

- Stimulates the liver to turn glucose into glycogen for storage

17

Where is testosterone produced, what is its role and what are the effects of it (3)

- Testes

- Main male sex hormone

- Promotes male secondary sexual characteristics, e.g facial hair

18

Where is progesterone produced, what is its role and what are the effects of it (3)

- Ovaries

- Supports pregnancy

- Maintains the lining of the uterus

19

Where is oestrogen produced, what is its role and what are the effects of it (3)

- Ovaries

- Main female sex hormone

- Controls the menstrual cycle, promotes secondary sexual characteristics, e.g widening of the hips

20

What are the differences between nerves and hormones (3)

- Nerves : very fast message, hormones : slower message

- Nerves : act for a very short time, hormones : act for a long time

- Nerves : act on a very precise area, hormones : act in a more general way

21

For these circumstances, is it nerves or hormones that carry out the response (5)

1. If the response is really quick

2. If some information needs to be passed to effectors really quickly

3. If the response lasts for a long time

4. When you get a shock

1, 2 - nerves

3,4 - hormones

22

What is homeostasis (1)

- Homeostasis is the maintenance of a constant internal enviornment

23

Two examples of homeostasis (4)

- Water content (balance between water you gain and water you lose)

- Body temperature (rid of excess body heat when hot, retain heat when the environment is cold)

24

Give three ways water is lost from the body (6)

 

- through the Skin (as sweat)

- via the Lungs (as breath)

- via the Kidneys (as urine)

25

What temperature do enzymes work best at (1)

- 37 degrees

26

What body part maintains homeostasis of body temperature (3)

- CNS

- Signals from receptors in the skin

- Activates necessary effectors to maintain homeostasis

27

What has a larger surface area to volume ratio : small or large organsims (1)

- small

28

Why is it an advantage/disadvantage for smaller organisms to have a high surface area to volume ratio (3)

- Can gain/lose heat faster because there is more area for the heat to transfer across

- Lose body heat more easily in hot climates (don't overheat)

- Very vunreable in cold enviornments 

 

 

29

How are animals living in cold conditions adapted (3)

- Compact (rounded) shape

- Keeps surface area to a minimum

- Reduces heat loss

30

What are auxins (3)

- Plant hormones

- Control growth at the tips of roots/shoots

- Move through the plant dissolved in water