Stimuli and responses

Question 1

Autonomic nervous system

Answer 1

a division of the peripheral nervous system that controls unconscious activities e.g. heart rate

Question 2

Atrioventricular node (AVN)

Answer 2

group of cells in the heart wall responsible for passing waves of electrical activity from the SAN to the bundle of His

slight delay before the AVN reacts to make sure the atria have emptied before the ventricles contract

Question 3

bundle of His

Answer 3

group of muscle fibres in the heart responsible for conducting waves of electrical activity from the AVN to the Purkyne fibres

Question 4

choice chamber

Answer 4

container with different compartments that can be used to investigate how animals respond to different environmental conditions

Question 5

cone cell

Answer 5

a photoreceptor cell found packed together in the fovea - 3 types each containing a different optical pigment (red-sensitive, green-sensitive, blue-sensitive) stimulated in different proportions
allows colour vision (trichromatic)
less sensitive to light because 1 cone joins 1 neurone so it takes more light to reach threshold and trigger action potential
high visual acuity because cones are close together + each cone triggers an action potential when light hits 2 cones

Question 6

rod cell

Answer 6

a photoreceptor cell found in the peripheral parts of the retina
give information in black and white (monochromatic)

very sensitive to light (work well in dim light) because many rods join 1 neurone so many weak generator potentials combine to reach threshold and trigger an action potential

low visual acuity because many rods join the same neurone so light from 2 points close together cannot be told apart

Question 7

coordinator

Answer 7

processes information from stimulus and sends impulses to effector along a motor neurone (e.g. CNS - brain + spinal cord)