Homestasis

Question 1

What is the definition of Homeostasis

Answer 1

The maintenance of a relatively stable internal state despite external fluctuations.

Question 2

What is a tolerance limit?

Answer 2

Tolerance limits consist of the upper and lower limits of a particular environmental condition which allows a certain species to survive

Question 3

Name 5 examples of tolerance limits in humans

Answer 3

1. Blood glucose level
2. Blood carbon dioxide and oxygen levels
3. Water and solute balance
4. Body temperature

Question 4

Name 2 examples of tolerance limits in plants

Answer 4

1. Solute Concentration

2. Water Concentration

Question 5

What is a biotic factor?

Answer 5

A living component of an ecosystem

Question 6

What is an abiotic factor?

Answer 6

A non-living component of an ecosystem

Question 7

Name two abiotic factors

Answer 7

wind, water

Question 8

Name two biotic factors

Answer 8

Flaura and fauna

Question 9

Define a stimulus

Answer 9

A stimulus is any change in the internal or external environment that can be detected

Question 10

Define a receptor

Answer 10

A receptor is a specialised cell or group of cells

Question 11

Define an effector

Answer 11

A muscle or gland that brings about a response

Question 12

Define the stimulus-response model in order

Answer 12

Stimulus, Receptor, Transmission of message, Effector, Response.

Question 13

Describe the role of sensory receptors

Answer 13

Sensory receptors detect stimuli such as light, chemicals, sound, temperature and touch

Question 14

Describe the role of effectors

Answer 14

An effector is a muscle or gland that carries out a response, such as movement or secretion, as a result of a stimulus

Question 15

What is a homeostatic control mechanism?

Answer 15

Self regulating mechanisms that involve negative feedback

Question 16

What is negative feedback?

Answer 16

A response that inhibits the stimulus that caused it

Question 17

Give an example of negative feedback?

Answer 17

Blood sugar regulation

Question 18

What is positive feedback?

Answer 18

A response that that increases the stimulus that caused it.

Question 19

Give an example of positive feedback?

Answer 19

Blood clotting

Question 20

Function of Sensory Neuron

Answer 20

Transmit information from a receptor to the CNS

Question 21

Function of Inter-Neuron

Answer 21

Transmit information from sensory neurons to motor neurons (link)

Question 22

Function of Motor-Neuron

Answer 22

Transmit messages from the CNS to effectors

Question 23

Structure of Sensory Neuron

Answer 23

cell body joined by two long sections. The Dendron (an extension of the dendrites transmit information towards the cell body), and axon

Question 24

Structure of Inter-Neuron

Answer 24

Have short axons as they enable connections between a sensory and motor neuron.

Question 25

Structure of Motor-Neuron

Answer 25

Usually have short dendrites and one long axon

Question 26

Define the Central Nervous System

Answer 26

Consists of the brain and spinal cord. Used for storing, arranging and managing information

Question 27

Define the Peripheral Nervous System

Answer 27

Consisting of all nerves other than the brain and spinal cord. Used for transmission of information to and from the CNS.

Question 28

State the function of a neurotransmitter

Answer 28

Binding of neurotransmitters to complementary receptors initiates a nerve impulse that travels along the axon of a post synaptic cell.

Question 29

Define a hormone

Answer 29

Chemicals produced by the endocrine system, transported by the circulatory system that have an effect on target cells through complementary binding to cell receptors

Question 30

Define metabolism

Answer 30

Collection of chemical reactions that occur within cells. E.g. respiration for thermoregulation