Homeostasis

Question 1

What is homeostasis?

Answer 1

Maintaining a constant internal environment
Inside of the cell
Within an organism

Question 2

Stimuli

Answer 2

A change in the internal or external environment

Question 3

Receptor

Answer 3

Cells that detect a stimuili

Question 4

Coordination

Answer 4

Decides how to respond

Question 5

Effector

Answer 5

Causes the response

Question 6

What is a nervous response?

Answer 6

Response which uses an electrical impulse
To bring out fast, but short-lived responses
Co-ordinated by our brain and spinal cord
And our nerves or neuron’s

Question 7

Reflexes

Answer 7

Involuntary response to a stimuli
Do not involve the conscious part of the brain
Include breathing, digestion and dropping g hot pans

Question 8

What is a reflex arc?

Answer 8

The nerve pathway that bypasses the conscious part of the brain
Made up of 3 nerve cells

Question 9

What is a synapse?

Answer 9

A microscopic gap
Between the ends of two nerves
Where chemical messengers(neurotransmitters) travel across

Question 10

Medulla:brain

Answer 10

Located in the brain stem, in front of the cerebellum
Responsible for unconscious activities

Question 11

Cerebellum:brain

Answer 11

Located at the bottom of the brain, with the cerebral cortex above
Responsible for balance and muscular activity

Question 12

Cerebral cortex:brain

Answer 12

Outer layer of the main sections of the brain
Responsible for more complex activities

Question 13

Thermoregulation

Answer 13

The process that allows your body to maintain it’s core internal temperature
Monitored and controlled by thermoregulatory centre
In hypothalamus

Question 14

Vasoconstriction

Answer 14

Muscle wall of blood vessels near the skins surface contract
Blood vessels narrow
Less blood flows through
Less blood reaches the surface of the skin
Less heat is lost by radiation
Warm up

Question 15

Vasodilation

Answer 15

Muscle wall of blood vessels near the skins surface relax
Blood vessels widen
More blood flows through
More blood reaches the surface of the skin
More heat is lost by radiation
Cool down

Question 16

Accomodation

Answer 16

Changing the shape of the lens
To focus on a near or distant object
By contracting and relaxing

Question 17

Hyopia

Answer 17

Short sightedness
Cannot focus on distant objects

Question 18

Hyperopia

Answer 18

Long sightedness
Cannot focus on those objects

Question 19

What are hormonal responses?

Answer 19

Slower but longer lasting responses
Caused by hormones
Released from glands
Travel in the blood to their target organ

Question 20

How do we control our blood sugar levels?

Answer 20

Insulin-lowers blood sugar levels
Glucagon-Increases blood sugar levels
Both secreted from the pancreas
Work antagonistically

Question 21

Ultrafiltration

Answer 21

Only the small things can pass through to form the urine
Protein stays in the blood as it it too big

Question 22

How do we loose water from our bodies?

Answer 22

The lungs during exhalation
Skin in sweat
Excess water, ions and urea are removed via the kidney in the urine

Question 23

Why must we control water loss?

Answer 23

To much water moving into animal cells cause them to burst
Too much water leaves a cell they shrivel up
This damage affects the cells function