B10 THE NERVOUS SYSTEM

Question 1

What is your internal enviroment

Answer 1

The conditions inside your body

Question 2

What is homeostasis

Answer 2

The process of keeping everything constant inside yout body(internal envrioment has to stay the same)

Question 3

What is controlled through homeostasis (3 things)

Answer 3

Internal body temprature
Water levels
Sugar levels

Question 4

What are receptor cells

Answer 4

Speciallised cells which detect a change in the environment (stimulus) and stimulate electrical impulses in response

Question 5

What is the coordination centre and example

Answer 5

receives and processes information from receptors around the body(brain and spinal cord)

Question 6

What are effectors

Answer 6

include muscles and glands - that produce a specific response to a detected stimulus

Question 7

What is the nervous system

Answer 7

System which controls all the actions which are body makes

Question 8

What does the cns include

Answer 8

Brain and spinal cord

Question 9

What does the peripheral nervous system include and what does it do

Answer 9

Contains nerves taking info from the sense organs to the cns and back to the effectors

Question 10

Detailed explanation on the nervous system

Answer 10

Info passes along cells called neurones as electrical impulses to the cns.(bunches of neurones are called nerves.) the cns coordinates the response of effectors which may be muscles contracting or glands secreting hormones

Question 11

The nervous system journey

Answer 11

Stimulus–> receptor–> sensory neurone—>coordination (cns)–>motor neurone—->effector——->response

Question 12

Types of neurone explanations

Answer 12

First neurone in the chain is the sensory neurone. It’s connected to the receptor and carries the message to the cns

The second neurone is the motor neurone. Which carries messages from the cns and is connected to the effector

Question 13

What are reflex actions

Answer 13

Actions are automatic. Messages bypass the brain. We do them without thinking, involuntarily

Question 14

What is the relay neurone

Answer 14

Passes electrical impulses from the sensory neurone to the motor neurone found in the spinal cord and brain

Question 15

Nervous system journey but with a reflex action

Answer 15

Stimulus–> receptor–> sensory neurone—> relay neurone–>motor neurone—->effector——->response

Question 16

What is the synapse

Answer 16

The gap where 2 neurones conmect

Question 17

How do electrical impulses travel through the synapse

Answer 17

They Travel to one end of the nerve cell and cause a chemical to be released called a neurotransmitter this diffuses across the gap more slowly than an electrical impulse would travel.

Question 18

Reaction time required practical method

Answer 18

1-One student holds a ruler vertically so the zero end points downwards. The other student puts their thumb and fingers in a C shape around the ruler, level with the zero marking (weakest hand)
2=Without warning, the first student drops the ruler and the second student has to catch it as quickly as they can.
3=Write down the number just above the second student’s thumb. The lower the number, the shorter the reaction time. Write the number in the results table and convert it into a reaction time in ms.
4=Repeat steps 2 to 4 four more times.
5=Now repeat but cause a distraction in the room.
6-Repeat steps 2 to 4 five more times and record the results in the table.
7-Calculate the mean. giving your answer to the nearest whole number.
8-Plot your mean results in a bar chart