homeostasis + CNS/PNS

Question 1

define homeostasis

Answer 1

the maintenance of the constant internal environment

Question 2

Recall different types of receptors

Answer 2

type of receptors: mechanoreceptors, chemoreceptors, thermoreceptors, photoreceptors

stimuli it responds to: 1:pressure(touch) and sound 2: chemicals 3: temperature 4: light

where in the body: 1: skin, ear 2: tongue, nose 3: skin 4: eye

Question 3

Explain homeostasis using the stimulus response model

Answer 3

To achieve homeostasis (balance), the body needs to respond to changes within the body’s internal and external environment. Changes are detected by receptors within a body, and if a response is required, then actions are brought about by effectors to bring the body back to equilibrium (balance).
stimulus —–> receptor ——> control Centre/transmission molecules ——> effector ——–> response ——–> feedback (usually negative) ——> stimulus (back to starting point

Question 4

Differentiate between negative and positive feedback

Answer 4

Negative feedback is most common and aims to reduce the stimulus while positive feedback is uncommon and aims to increase the stimulus (take away from homeostasis)

Question 5

Differentiate between the CNS and the PNS

Answer 5

CNS is composed of the brain and spinal chord, PNS is composed of the nerves that connect the CNS to the rest pf the body (all the other nerves in the body). CNS has a major role in controlling activity of other organs and the PNS relays info to and from the CNS. The PNS can be dividing into autonomic and somatic systems.

Question 6

Differentiate between autonomic and somatic systems

Answer 6

Somatic system is voluntary while autonomic is involuntary (reflex)