5.1.5 Plant and animal responses

Question 1

Which neurotransmitter is present in the somatic nervous system?

Answer 1

Acetylcholine - stimulatory effect

Question 2

Which neurotransmitter is present in the sympathetic system?

Answer 2

Noradrenaline

Question 3

Which neurotransmitter is present in the parasympathetic system?

Answer 3

Acetylcholine

Question 4

What is the function of the cerebrum?

Answer 4

Controls voluntary actions such as learning, memory, personality and conscious thought

Question 5

What is the function of the cerebellum?

Answer 5

Controls unconscious functions such as balance and non voluntary movement

Question 6

What is the function of the medulla oblongata?

Answer 6

Used in autonomic control e.g. controls heart rate and breathing rate

Question 7

What is the function of the hypothalamus?

Answer 7

Regulatory centre for temperature and water balance

Question 8

What is the function of the pituitary gland?

Answer 8

Stores and releases hormone

Question 9

What is the function of the anterior (front) pituitary?

Answer 9

Produces FSH

Question 10

What is the function of the posterior (back) pituitary?

Answer 10

Stores and releases hormones produced by hypothalamus e.g. ADH

Question 11

What is the pathway of a reflex arc?

Answer 11

Receptor -> sensory neurone -> relay neurone -> motor neurone

Question 12

What is the stimulus in the knee jerk reflex?

Answer 12

Tapping the patella and causing the patellar tendon to stretch

Question 13

In the knee jerk reflex the ______ muscle contracts and the ______ relaxes causing the leg to kick

Answer 13

Extensor
Flexor

Question 14

What is the stimulus in the blinking reflex?

Answer 14

• Cornea being touched (corneal reflex)
• Loud sound
• Bright light (optical reflex)

Question 15

What type of reflex is the knee jerk reflex?

Answer 15

Spinal (occurs in the spinal cord)

Question 16

What type of reflex is the blinking reflex?

Answer 16

Cranial (occurs in the brain)

Question 17

What is the effector in the blinking reflex?

Answer 17

Eyelid

Question 18

What is the importance of reflexes?

Answer 18

• Minimises harm to body by being a very fast response
• Doesn’t have to be learnt so provides immediate protection form birth
• Doesn’t require conscious thought so brain is not overstimulated

Question 19

What are the three types of muscles?

Answer 19

• Skeletal muscle
• Cardiac muscle
• Involuntary muscle (smooth muscle)

Question 20

What is the structure and arrangement of skeletal muscle?

Answer 20

• Striated fibres (lines on fibres)
• Tubular fibres which are multinucleated (more than one nucleus) and regularly arranged

Question 21

What is the contraction length and speed in skeletal muscle?

Answer 21

Short and rapid in one direction

Question 22

What is the structure and arrangement of cardiac muscle?

Answer 22

• Specialised striated fibres (less lines on fibres than skeletal)
• Branched fibres which are uninucleated (only one nucleus)

Question 23

What is the structure and arrangement of involuntary muscle?

Answer 23

• Non-striated fibres
• Spindle shaped fibres which are uninucleated (only one nucleus) with no regular arrangement

Question 24

What is the contraction length and speed in involuntary muscle?

Answer 24

Long and slow in different directions

Question 25

What is the plasma membrane which encloses muscle fibres?

Answer 25

Sarcolemma

Question 26

What is the shared cytoplasm between muscle fibres called?

Answer 26

Sarcoplasm

Question 27

What are T tubules and what is their function?

Answer 27

Parts of the sarcolemma that fold in to help spread electrical impulse through sarcoplasm so entire fibre can contract

Question 28

Why do muscle fibres have a lot of mitochondria?

Answer 28

Provide ATP needed for muscle contraction

Question 29

What does the sarcoplasmic reticulum contain?

Answer 29

Calcium ions required for muscle contraction

Question 30

What types of protein filaments are myofibrils made of?

Answer 30

Actin - thinner Myosin - thicker

Question 31

What are I bands?

Answer 31

The lighter coloured bands where only actin is present and there is no overlap between the myosin filaments and actin

Question 32

What are A bands?

Answer 32

The darker coloured bands where there is myosin present and an overlap between myosin filaments and actin

Question 33

What is a Z line?

Answer 33

Line found at the centre of the light band

Question 34

What is the distance between adjacent Z lines called?

Answer 34

Sarcomere

Question 35

What is the H zone?

Answer 35

Lighter coloured region in centre of dark band where only myosin filaments are present