16
During resting potential, the axonal membrane is polarised, indicate the movement of +ve and -ve ions leading to polarisation diagrammatically.
Explanation
17
Name the structures involved in the protection of the brain.
Explanation
The following structures are involved in the protection of brain in animals
(i) Cranium There are 8 cranial bones which form the hard protective outer covering cranium for the brain.
(ii) Meninges The brain is covered with three membranes called meninges.
(a) Piamater Inner most membrane very thin, delicate and vascular and invests the brain closely.
(b) Arachnoid membrane It is like spider we in structure from which its gets its name.
(c) Duramater It is outer most, thick, tough fibrous membrane adhering closely to the inside of the skull.
(iii) Cerebrospinal fluid The cerebrospinal is present in the spaces between the meninges, i.e., arachnoid and duramater, which functions as a pad, absorbing shocks.
18
Our reaction like aggressive behaviour, use of abusive words, restlessness etc. are regulated by brain, name the parts involved.
Explanation
The inner part of cerebral hemispheres and a group of associated deep structures called limbic lobe or limbic system along with hypothalamus are involved in the above said functions, i.e., aggressive behaviour, use or abusive words, restlessness, etc.
19
What do grey and white matter in the brain represent?
Explanation
Grey matter is a major component of CNS consisting of neuronal cell bodies, dendrite, unmyelinatedaxous, glial cells and capillaries.
White matter is also a component of CNS and consists mostly of glial cell and myelinated axons.
20
Where is the hunger centre located in human brain?
Explanation
Hypothalamus contains many centres which control urge for eating and drinking.