Biology - Homeostasis

State 3 factors that are controlled by homeostasis in the human body. (3)

● Blood glucose concentration

● Body temperature

● Water levels

Which kind of cells detect stimuli? (1)

Receptors

What processes the information received from the receptors? (1)

Coordination centres

State the 3 coordination centres in the human body. (3)

● Brain

● Spinal cord

● Pancreas

What brings about responses to bring the conditions in the body back to optimum levels? (1)

Effectors

State the 2 types of effectors in the human body. (2)

● Muscles

● Glands

What does the nervous system allow us to do? (2)

● React to our surroundings

● Coordinate actions in response to stimuli

What is the name of of the automatic responses which take place before you have time to think? (1)

Reflexes

Give 2 examples of reflex arcs. (2)

● Pupils getting smaller to avoid damage from bright lights

● Moving your hand from a hot surface to prevent damage

What is the name of the gaps between 2 neurons? (1)

Synapse

What is reaction time, and how can it be measured? (2)

● How long it takes to respond to a stimulus

● It can be measured with the ruler drop test

Name the three components of the brain. (3)

Cerebral cortex

Cerebellum

Medulla

State the function of the cerebral cortex and where it is. (2)

Controls consciousness, intelligence, memory and language

It’s the outer part of the brain

State the function of the cerebellum and where it is. (2)

Controls fine movement of muscles

Rounded structure towards the bottom/back of the brain

State the function of the medulla and where it is. (2)

Controls unconscious actions such as breathing and heart rate

Found in the brain stem in front of the cerebellum

Explain why investigating the brain function and treating brain damage and disease is difficult? (4)

It’s complex and delicate

It’s easily damaged

Drugs can’t always reach the brain because of the membranes surrounding it

It’s not fully understood which part of the brain does what

State how neuroscientists can map out the regions of the brain (3)

● Study brain damage

● Electrically stimulating different parts of the brain

● Using MRI scanning techniques

How does the eye focus on a nearby object? (3)

● The ciliary muscles contract

● The suspensory ligaments loosen

● The lens is then thicker, more curved and refracts the light more

How does the eye focus on a distant object? (3)

● The ciliary muscles relax

● The suspensory ligaments tighten

● The lens then becomes thinner and light is refracted

State the name for short-sightedness. (1)

Myopia

State the name for long-sightedness. (1)

Hyperopia

What causes myopia? (2)

● Lens is too curved

● So distant objects appear blurry

What causes hyperopia? (2)

● The lens is too flat

● It can’t refract light enough

Name the 4 treatment methods for eye defects. (4)

● Spectacle lenses

● Contact lenses

● Laser eye surgery

● Replacement lens

State where the thermoregulatory centre is found. (1)

The brain

What do the receptors in the thermoregulatory system do? (2)

Monitor the temperature of the blood

Skin receptors send impulses to the thermoregulatory centre

Describe what will happen if human body temperature is too high. (2)

Sweat is produced from sweat glands

Vasdilation - more blood flows closer to the skin

Describe what will happen if human body temperature is too low. (4)

Sweating stops

Skeletal muscles contract rapidly to generate heat

Hairs stand on end to create an insulating layer

Vasocontriction - blood does not flow so close to the surface