Biology Topic 8 (Brain Structure and Function (Brain Area and Function…
Biology Topic 8
Brain Structure and Function
Brain Area and Function
Has a thin outer layer (the cerebral cortex), which has a large surface area, highly folded allowing it to fit in the skull.
The Cerebrum is involved in vision, learning, thinking, emotions and movement.
Different parts of the cerebrum are involved in different functions - the back of the cortex is involved in vision and the front is involved in thinking.
The largest part of the brain, divided into 2 halves - cerebral hemispheres
Is found just beneath the middle part of the brain
it automatically maintains body temperature at he normal level - thermoregulation
Produces hormones that control the pituitary gland - a gland just below the hypothalamus
the Medulla Oblongata
At the base of the brain, at the top of the spinal cord
Automatically controls breathing rate and heart rate
Underneath the cerebrum and also has a folded cortex
Important for coordinating movement and balance
Computed Tomography (CT)
Use radiation (X-rays) to produce cross-section images of the brain. Denser structures in the brain absorb more radiation than those which are less dense, showing up lighter and darker in the scan
Magnetic Resonance Imaging (MRI)
Use strong magnetic fields and radio waves to produce a 3D and cross sectional images of the brain
functional Magnetic Resonance Imaging (fMRI)
More oxygenated blood flows to active areas of the brain (providing active cells (neurones) with oxygen and glucose. molecules in oxygenated blood respond differently to a magnetic field than those in deoxygenated blood - a signal being stronger from oxygenated blood and so more active areas can be identified.
Positron Emission Tomography (PET)
A radioactive tracer is introduced to the body (more invasive than other scans) and is absorbed into tissues. The scanner detects the radioactivity of the tracer, building a map of the radioactivity in the brain. Different tracers can be used.