The Human Brain 5.5.9 Flashcards
What is the brain part of?
The central nervous system
What is the brain composed of? (basic)
Billions of interconnected neurones
What is the function of the brain?
Controlling complex behaviours
What are the 5 regions of the brain?
- Cerebrum
- Hypothalamus
- Pituitary gland
- Cerebellum
- Medulla oblongata
What does the cerebrum control?
Voluntary actions (concious activities)
- Thought
- Speech
- Memory
- Problem solving
What does the cerebellum control?
Responsible for muscle coordination and movement
What does the medulla oblongata control?
Controls involuntary actions (unconcious activities)
e.g. heart rate and breathing rate
What does the pituitary gland control?
‘Master gland” responsible for regulating many body functions, controlling the activity of other glands
What does the hypothalamus control?
Control centre that monitors blood and helps maintain homeostasis
What does the cerebrum consist of, and how is it divided?
Five lobes - divided into two halves, known as the cerebral hemisphere
What are the cerebral hemispheres joined together by?
A band of nerve fibres, known as the corpus callosum
What does the right hemisphere control?
The left side of the body
What does the left side of the body control?
The right side of the body
What is the thin outer layer of the cerebrum called?
The cerebral cortex or ‘grey matter’
What does the cerebral cortex consist of?
Cell bodies of neurones
How is the cerebral cortex adapted to its function?
It’s highly folded, which increases its surface area and allows it to contain a greater number of neurones.
This means that more connections can be made between neurones and therefore increases the ability of the brain to carry out more complex behaviours
What is located beneath the cerebral cortex?
The ‘white matter’
What is the white matter composed of?
Consists of the myelinated axons of neurones
Where is the hypothalamus found?
Just above the pituitary gland (which it is connected to)
What are the main functions of the hypothalamus?
- Regulating body temperature
- Osmoregulation
- Regulating digestive activity (controls the secretion of enzymes inn the gut and peristalsis)
- Controlling endocrine functions (hypothalamus releases chemicals that cause the pituitary gland to release certain hormones)
How does the hypothalamus regulate body temperature?
Monitoring blood temperature and initiating a homeostatic response
How does the hypothalamus carry out osmoregulation
Monitoring how concentrated the blood is, and if it becomes too concentrated ADH is released, it also generates a feeling of thirst
How does the hypothalamus regulate digestive activity?
Controls the secretion of enzymes in the gut and peristalsis - also generates a feeling of hunger
How does the hypothalamus control endocrine functions?
Releases chemicals that cause the pituitary gland to release certain hormones that control a variety of processes (metabolsm, growth and development, sleep, mood)
Where is the pituitary gland located?
At the bottom of the brain, below the hypothalamus
What is the pituitary gland divided into?
The anterior pituitary and posterior pituitary
What is the function of the anterior pituitary?
Produces and releases certain hormones
What is the function of the posterior pituitary?
Stores and releases hormones produced by the hypothalamus (ADH and oxytocin)
Where is the cerebellum located?
Lies below the cerebrum
What does the cerebellum control?
Motor coordination - includes balance
These functions are only subconsciously (involuntary)
Where is the medulla oblongata found?
At the very base of the brain
What three centres composes the medulla?
- Cardiac - controls heart rate
- Vasomotor - controls blood pressure
- Respiratory - controls respiratory rate
What does the cardiac centre control?
Heart rate
What does the vasomotor centre control?
Blood pressure, by controlling the contraction of smooth muscles in arteriole walls
What does the respiratory centre control?
Breathing rate (contains an inspiratory centre and an expiratory centre)
