AQA Biology Unit 5: Chapter 9 Response to Stimuli

What is a stimulus?

What is a receptor?

What is an effector?

What is a coordinator?

What is meants by the term taxes?

What is the difference between a positive or negative taxes?

What is kinesis and what is its purpose?

What is a trophic response?

What is meant by the following terms:
a) Positive phototropism;
b) Negative phototropism;
c) Negative hydrotropism;

What does the central nervous system compose of?

What does the peripheral nervous system compose of?

What is the peripheral nervous system further divided into?

Which two types of neurones are involved in the peripheral nervous system?

What function do sensory neurones carry out?

What function do motor neurones carry out?

What is the difference between the somatic (voluntary) and automatic nervous system?

Describe the sequence of a reflex arc, use the example of touching a hot object

Describe the importance of a reflex arc

What is the automatic nervous system divided into?

Why are the parasympathetic and sympathetic nervous systems described as being antagonistic?

Generally, what does the parasympathetic nervous system do?

Generally, what does the sympathetic nervous system do?

What are changes in heart rate controlled by?

Describe the medulla oblongata

What is the centre to increase heart rate (in the medulla oblongata) linked to the sinoatrial node by?

What links the centre to decrease heart rate in the medulla oblongata to the sinoatrial node?

Which two things determine which centre in the medulla onlongata is stimulated?

Where are chemorecptors found, and what are they receptive to?

Describe the process of events which occur when the blood has a higher than normal concentration of carbon dioxide, in order to return carbon dioxide concentration back to normal levels

Describe how blood pH is maintained at a normal level

Where are the pressure receptors found?

What happens when blood pressure is higher than normal?

What occurs when blood pressure is lower than normal?

What is the pacinian corpuscle sensitive to?

What is meant when the pacinian corpuscle is described as a transducer?

Describe the structure of the pacinian corpuscle

Explain how a pacinian corpuscle functions

In what part of the eye are light receptors found?

What do receptors in the eye do?

Describe the structure of rod cells:

Describe the structure of a cone cell:

What type of vision do rod cells give, why?

Why do rod cells give poor visual acuity?

What is retinal convergence and what does it allow?

In addition to retinal convergence what else allows rod cells to work in low light intensity?

What must happen for a generator potential to be produced in rod cells?

What type of vision do cone cells give, why?

Compare the number of rod cells and cone cells:

Where about in the cornea are rod cells and cone cells found?

Why do cone cells give good visual acuity?

Why do cone cells only work in high light intensity?