2024 T4 Science revision Flashcards
(14 cards)
What are the five senses and their associated organs?
Sight: Eye
Hearing: Ear
Taste: Tongue
Smell: Nose
Touch: Skin
What are the key structures in the ear and eye?
Ear: Pinna, ear canal, eardrum, ossicles, cochlea
Eye: Cornea, iris, lens, retina, optic nerve
How does the ear detect sound?
Sound waves travel through the ear canal, hit the eardrum, are amplified by ossicles, and are processed in the cochlea, where they are converted into nerve signals for the brain.
How does the eye detect light?
Light enters the eye, passes through the cornea, is focused by the lens onto the retina, where rods and cones convert it into nerve impulses sent to the brain.
What are the main structures of a neuron, and how do neurons function?
Neurons have a cell body, dendrites, axon, and synaptic terminals. They transmit information via electrical signals, passing across synapses using neurotransmitters.
Describe the stimulus response model.
A stimulus, such as touching a hot surface, triggers a receptor, which sends a signal to the brain, resulting in a response like pulling your hand away.
What is a reflex action?
A rapid, involuntary response that protects the body, like blinking when something approaches your eye.
What are the roles of the Central and Peripheral Nervous Systems?
CNS: Brain and spinal cord, processes information.
PNS: Connects the CNS to limbs and organs.
Somatic: Controls voluntary actions.
Autonomic: Controls involuntary actions like heart rate
What are the main brain lobes and their functions?
Frontal: Decision-making
Parietal: Sensory information
Temporal: Hearing
Occipital: Vision
What is homeostasis?
The body’s maintenance of stable internal conditions, which is crucial for proper function.
How does the endocrine system support homeostasis?
It includes glands like the pituitary, which release hormones to regulate processes such as growth and metabolism.
How do hormonal responses differ from nervous responses?
Nervous responses are quick and short-lived, while hormonal responses are slower but last longer.
What is the role of negative feedback loops in the body?
They help regulate body processes by reversing changes, like stabilising blood sugar levels.
2Give examples of homeostasis in the body.
Blood glucose: Regulated by insulin and glucagon.
Water content: Managed by kidneys and hormones.
Body temperature: Maintained through sweating or shivering.
