Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • NCERT
  • Write short notes on the following: (b) Forebrain

Q5.    Write short notes on the following:

         (b) Forebrain

Answers (1)

The forebrain consists of these three:

Cerebrum, Thalamus and Hypothalamus.

Cerebrum:

  • The forebrain
  • It forms the major part of the brain.
  • The cerebrum is divided into halves longitudinally by a deep cleft. Each half is called a cerebral hemisphere.
  • Both hemispheres are connected by the corpus callosum-a tract of nerve fibres.
  • The cerebral hemispheres are hollow internally.
  • The walls of the cerebrum have an outer cortex and an inner medulla.
  • The cerebral cortex contains cell bodies of neurons and hence appears greyish. It is called grey matter.
  • The grey matter is thrown into many grooves and folds called sulci and gyri, respectively.
  • A higher number of convolutions leads to greater intelligence.
  • The cerebral cortex contains motor areas, sensory areas and association areas. Association areas are neither sensory nor motor.
  • These areas are responsible for complex functions such as memory, communication and intersensory associations.
  • The cerebral medulla consists of axons of nerve fibres and appears whitish. It is called white matter.
  • The inner part of the cerebral hemispheres and a group of associated deep structures such as hippocampus and amygdala form a complex structure called the limbic lobe or limbic system.
    • Functions:
    • The cerebrum is the centre of intelligence, memory, consciousness, will power and voluntary actions.

Thalamus:

  • It is made of grey matter.
  • It is situated superior to the midbrain.
  • Functions:
    • The thalamus relays motor and sensory impulses to the cerebrum.
    • It also regulates the manifestation of emotions and recognises heat, cold and pain.

Hypothalamus:

  • It lies at the base of the thalamus.
  • It consists of the optic chiasma, a point where the fibres of optic nerves cross to opposite sides.
  • Behind the optic chiasma is the infundibulum. It is a greyish protuberance of the hypothalamus.
  • The infundibulum holds the pituitary gland.
  • Functions:
    • The hypothalamus contains the centres which control body temperature, blood pressure and homeostasis.
    • It contains the centres to control hunger, thirst, sleep, fatigue, emotions, anger, pleasure and penance.
    • The neurosecretory cells of the hypothalamus secrete certain hormone or releasing factors which control the activity of the pituitary hormones.
    • The hypothalamus along with the limbic system is involved in the regulation of sexual behaviour. 
Posted by

Priyanka Kumari

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads

Similar Questions

Trending Articles/News

anam-khan

CBSE Class 12 board exams 2025 to have 50% competency-based questions; no change in 10th
anam-khan

CBSE Class 12 board exams 2024 over; expected result date, trends of last 10 years

Latest Question