Nervous and Endocrine System WOT - Science T2 2026

Describe the stimulus response

Stimulus -> Receptor -> CNS (brain and spinal cord) -> Effector (via the interneuron and motor neuron) -> Response

Types of neurons

Sensory, motor and interneurons

Sensory neuron

Carries incoming information from the sensory receptors to the brain and spinal cord

Interneuron

Connects sensory and motor neurons

Motor neuron

Sends an impulse to a muscle or gland, causing the muscle or gland to react

What are the main parts of the neuron?

Dendrites, cell body (soma), axon, myelin sheath and axon terminals

Role of dendrites in nerve transmission

Receive incoming signals from other nerve cells

Role of the cell body in nerve transmission

Acts as the metabolic and integration center of a neuron

Role of the axon in nerve transmission

Conducts electrical impulses away from the cell body (soma)

Role of the myelin sheath in nerve transmission

increases the speed and efficiency of nerve impulse transmission

Role of axon terminals in nerve transmission

Carries impulses to other neurons

What is a synapse?

The gap between 2 nerve cells or neurons

What are neurotransmitters?

Chemicals that send messages across a synapse from one nerve cell to another

Describe synaptic transmission between neurons

1. Neurotransmitters are released from vesicles

2. The vesicles fuse with the cell membrane

3. The neurotransmitter travels across the synapse

4. The neurotransmitter binds to the receptor on the nearest dendrite

What are the 3 main parts of the brain?

The forebrain, midbrain and hindbrain

What are the 2 main parts of the hindbrain?

The brain stem (medulla) and cerebellum

What is the main part of the forebrain?

The cerebrum

Brain stem (medulla)

Regulates critical, involuntary survival functions

Cerebellum

Controls posture, coordination, balance and movement

Cerebrum

Controls conscious, voluntary activities such as thinking, memory, senses and voluntary movement

What are the 4 lobes of the brain?

Frontal lobe, parietal lobe, occipital lobe, temporal lobe (FPOT)

Functions of the frontal lobe

Controls decision-making, planning, personality, speech and voluntary movement

Functions of the parietal lobe

Processes touch, temperature and pain

Functions of the occipital lobe

Processes visual information and Interprets colour, shape, and movement

Functions of the temporal lobe

Where hearing is processed and where our memories are stored

What are reflex actions?

Automatic and rapid actions that travel through the spinal cord instead of the brain to ensure survival and protect the body from harm

Why are reflex actions important?

They protect the body from harm

What are the differences between reflex arcs and conscious thoughts?

Reflex arcs are automatic, quick responses that travel through the spinal cord to help you survive by protecting the body from harm whereas conscious thoughts are slow, deliberate and controlled by the cerebrum

What are some differences between the nervous and endocrine system?

Endocrine effects last longer, the nervous system is faster and shorter and the nervous system involves chemical and electrical messages whereas the endocrine only involves chemical messages

What are similarities between the nervous and endocrine systems?

They coordinate and control body functions, help maintain homeostasis, use chemical signals to communicate and both respond to stimuli

What are similarities between neurons and endocrine glands?

Both are specialised cells that produce chemical signals to communicate with other parts of the body and help coordinate body functions.

What are differences between neurons and endocrine glands?

Neurons transmit rapid electrical and chemical signals through the nervous system, while endocrine glands release hormones into the bloodstream

What are the major glands involved in the endocrine system?

Hypothalamus, adrenal glands, ovaries, pancreas, parathyroid glands, pineal gland, pituitary gland, testes and thyroid gland

What hormones does the pituitary gland produce?

Growth hormones, thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinising hormone and prolactin

What hormones does the thyroid gland produce?

T4 (thyroxine), T3 and calcitonin

What hormones does the hypothalamus produce?

ADH and oxytocin

What hormones does the adrenal gland produce?

Adrenaline, cortisol and aldosterone

What hormones does the ovaries produce?

Estrogen and progesterone

What hormones does the pancreas produce?

Insulin and glucagon

What hormones does the parathyroid produce?

Parathyroid hormone

What hormones does the pineal gland produce?

Melatonin and serotonin

What hormones does your testes produce?

Testosterone

Thyroxine

Controls your body's metabolism, heart rate, brain development, and bone maintenance

Testosterone

Drives male puberty, regulates sex drive, builds bone and muscle mass, and promotes red blood cell production.

Estrogen

Essential for reproductive development, bone strength, and brain health

Adrenaline

Triggers your "fight-or-flight" response and instantly prepares you for fast action by pumping your heart faster, opening up your breathing and giving you a sudden burst of energy

Insulin

Regulates blood sugar (glucose) levels by decreasing blood sugar

Glucagon

Prevents blood sugar from dropping too low by increasing blood sugar

Growth hormone

Fuels childhood growth, controls body composition, and regulates metabolism

What happens to the neurotransmitter after it crosses the synapse?

It breaks down or is reabsorbed

Why is there a synapse between neurons?

To allow control and flexibility in signalling

Describe the order of events at a synapse

Electrical -> Chemical -> Electrical

Where is the hindbrain located?

At the back and base of the brain

Which part of the forebrain helps relay messages between the body and the cerebrum?

Thalamus

Which part of the forebrain controls hunger, thirst, body temperature and emotions?

Hypothalamus

What does the parietal lobe help the brain do?

Understand space and body position

What are hormones?

Chemical messengers carried in the blood

What happens if the body doesn't produce enough insulin?

Diabetes