Biology Topic 5 - 1/2

Question 1

Define Homeostasis

Answer 1

To be able to maintain a stable internal environment by regulating your conditions internally and externally

Question 2

What is the function of your automatic control system in your body

Answer 2

Regulates your internal environment such as body temperature, blood glucose levels and water content

Question 3

What three things is your automatic control system made up of

Answer 3

Receptors
Coordination centre
Effectors
Neurones

Question 4

What happens during Negative Feedback

Answer 4

This is when your automatic control system keeps your internal environment stable. When the level of something gets too high or too low, your body uses negative feedback to bring it back to normal

Question 5

What happens when a Stimulus detects that something is too high

Answer 5

1. Receptor detects a stimulus as it is too high
2. The coordination centre receives it and processes the information and organises a response
3. Effectors produces a response which counteracts the change and restores back to optimum level

Question 6

What happens when a Stimulus detects that something is too low

Answer 6

1. Receptor detects a stimulus as it is too low
2. The coordination centre receives it and processes the information and organises a response
3. Effectors produces a response which counteracts the change and restores back to optimum level

Question 7

What does the Nervous system do

Answer 7

Detects and reacts to stimuli

Question 8

What does the Central Nervous System consist of

Answer 8

Consists of the brain and spinal chord

Question 9

Define sensory neurone

Answer 9

This neurone carries information as electrical impulses from the receptors to CNS

Question 10

Define motor neurone

Answer 10

This neurone carries information as electrical impulses from the CNS to effectors

Question 11

Define Effector

Answer 11

It is where all your muscles and glands respond to electrical impulses

Question 12

How does the muscles react to a stimulus

Answer 12

They contract in response to electrical impulses

Question 13

How does the glands react to a stimulus

Answer 13

Glands secrete hormones

Question 14

What is a synapses

Answer 14

the connection between 2 neurones where one neurone transmits impulses from electrical to chemical impulses as it diffuses across the gap then goes back to electrical impulse when it reaches the next neurone

Question 15

What are reflexes and how is it helpful

Answer 15

Reflexes are rapid, automatic responses to certain stimuli that dont involve using the brain to think which can prevent injuries

Question 16

What is a reflex arc

Answer 16

The passage of information from receptor to effector

Question 17

Describe the 6 stages of the reflex arc of a bee stinging a finger

Answer 17

1) The bee stings the finger
2) The receptor detects the stimulus
3) The information is sent along the sensory neurone to the CNS where it reaches a synapse and electrical impulses is transferred to chemical impulses as it diffuses through the gap to the relay neurone and then transfers back to electrical impulses
4) Then the information is sent from the relay neuron to motor neurone where electrical impulses transfer to chemical impulses as it diffuses through the gap then reaches the motor neurone as electrical impulse
5) Information is sent from motor neurone to effector (muscle)
6) The muscle then contracts and moves hand away from bee

Question 18

What makes your reaction time faster

Answer 18

Caffeine is a drug that can speed up a persons reaction time

Question 19

How can you investigate reaction time using a ruler drop test

Answer 19

1) person tested sits with arm resting on edge of table
2) Hold a vertical ruler between their thumb and forefinger with it in line with 0cm
3) let go without giving a warning
4) The person should catch it ASAP
5) The smaller the number they catch it on the faster their reaction time
6) Repeat several times and calculate mean distance

Question 20

What are 3!control variable should you control

Answer 20

Use same hand when catching
Use same person catching ruler
Ruler should be dropped from same height

Question 21

How can you investigate reaction time using a computer test

Answer 21

The person being tested has to click a mouse or press a key as soon as they see a stimulus on the screen like a change in colour

Question 22

How is computer test more precise

Answer 22

1) It gives more precise reaction time as it removes possibility of human error
2) Computer can record the reaction time in milliseconds
3) Removes possibility that the person can predict when the dropper is going to drop the ruler by reading body language