2.2 Control and communication (1)

Question 1

Why do multicellular organisms need communication systems

Answer 1

In order to survive the human body must be able to take information from the outside world and respond to it. Organs and systems within the body must be able to share information to coordinate processes

Question 2

Identify the two internal communication systems in the human body.

Answer 2

Nervous system
Endocrine system

Question 3

Identify the three main structures that make up the nervous system of an animal

Answer 3

Brain
Spinal cord
Nerves

Question 4

Identify the two structures that make up the central nervous system (CNS)

Answer 4

Central nervous system (CNS)= brain+spinal cord

Question 5

What is the function of the CNS

Answer 5

The CNS processes information from the sense organs, sends about messages along motor neutrons to bring about a response in either a muscle or a gland (part of endocrine system)

Question 6

What are the three main parts of the brain and state the function of each part

Answer 6

• Medulla, controls breathing and heart RATE
• Cerebrum, conscious thoughts, personality, problem solving, memories ect
• Cerebellum, co-ordination of balance

Question 7

What does the spinal cord do?

Answer 7

Links brain and nerves

Question 8

How is information transmitted along neurons?

Answer 8

Information is transmitted along neurons as electrical impulses

Question 9

What do the sense organs contain?

Answer 9

The sense organs contain receptors, these receptors pick up stimuli (info) about the enviorment

Question 10

What happens with the information that is picked up by the receptors

Answer 10

The information is then passed to the CNS. Depending on the info the body may need to respond

Question 11

What are the parts of the body which bring about a response to stimuli?

Answer 11

The parts of the body which bring about a response are called effectors

Question 12

What are effectors?

Answer 12

Effectors= Muscle or glands in the body

Question 13

Identify the tiny gaps that separate neurones from each other

Answer 13

Neurons do not come into physical contact with each other. They are separated by tiny gaps called synapses

Question 14

Explain stage one of the synapse diagram

Answer 14

1. Electrical impulse arrives at the end of the neutron

Question 15

Explain stage two of the synapse diagram

Answer 15

2.Impules cause vesicles containing neurotransmitters to fuse with the cell membrane

Question 16

Explain stage three of the synapse diagram

Answer 16

3. Neurotransmitters diffuse across the synapse

Question 17

Explain stage four of the synapse diagram

Answer 17

4. Neurotransmitters bind with receptors on the next neuron

Question 18

Explain stage five of the synapse diagram

Answer 18

5. Electrical impulse generated in the next neuron

Question 19

What is a reflex action

Answer 19

A reflex action is an automatic response to a stimuli that happens very fast. It does not involve the brain

Question 20

Describe the role of the CNS in processing and responding to information from the sense

Answer 20

Sensory neurons pick up a stimuli and transmit an impulse to the CNS which contains interneurons- This is where processing decides if a response is required or not.Many stimuli are detected and receive by to the CNS but not all are responded to, many are filtered out. If processing determines that a response is required, another impulse will then be sent.

Question 21

Identify two types of response triggered by a motor neuron

Answer 21

A muscle contraction to bring about movement or secretion from a gland releasing a chemical messenger (hormone.)

Question 22

Identify the sequence of neurons involved in a reflex arc

Answer 22

Sensory neuron - detects the stimulus
Inter neuron- Receives signal from the sensory neuron and passes it to the motor neuron
Motor neuron- Carries the signal to bring about a response
(SIM)