KM Tutorials Academy

Structure of the Brain

The cerebral cortex :

is involved in higher-level functions. The cerebral cortex is divided into two hemispheres. Each hemisphere controls one side of the body. The cerebral cortex controls emotions, thoughts, personality, intelligence and other higher-level functions, including memory and language. The cerebral cortex can be split into over 50 different areas, and each one has a particular function (e.g. speech area, emotion area).

The cerebellum :

controls movement. The cerebellum is involved in the control of balance, and the coordination of muscles and movement. Without the cerebellum, our movements would be quite erratic and uncoordinated.

The medulla oblongata:

is involved in unconscious control. The medulla controls the things which are not under conscious control, like heart rate and breathing rate. For example, the medulla produces adrenaline during exercise to help increase our heart rate.

The hypothalamus:

is involved in homeostasis. It helps maintain body temperature and produces hormones that control the pituitary gland.
The pituitary gland produces important hormones. For example, hormones involved in the menstrual cycle including FSH and LH are produced here.

BIOLOGY: Revision on Ear

1. Outer Ear:

Pinna (Auricle):
The visible part of the ear, shaped like a funnel, that collects sound waves and channels them into the ear canal.

Ear Canal (External Auditory Meatus):
A tube that leads from the pinna to the eardrum, protecting the eardrum and amplifying sound.

Eardrum (Tympanic Membrane):
A thin, membrane-like tissue that vibrates when sound waves hit it, transmitting these vibrations to the middle ear.

Earwax:
A natural lubricant that protects the ear canal from drying out and infection.

2. Middle Ear:

Ossicles:
Three tiny bones (malleus, incus, and stapes) that amplify and transmit vibrations from the eardrum to the inner ear.

Eustachian Tube:
A tube that connects the middle ear to the back of the throat, helping to equalize pressure between the middle ear and the outside environment.

3. Inner Ear:

Cochlea:
A spiral-shaped, fluid-filled organ that converts vibrations into electrical signals.

Vestibular System:

Includes the semicircular canals and otolith organs, which are responsible for balance and spatial orientation.

Auditory Nerve:
Transmits the electrical signals from the cochlea to the brain for interpretation as sound.