what do u mean by concentration gradient?

Draw labelled diagrams of the following:

(a) Neuron (b) Brain (c) Eye (d) Ear

structure of brain

what is a nerve impulse ? how it is conducted hrough a nerve fibre ? mention any 2 factors which can increase the velocity of a nerve fibre ?

name the fluid present in the cochlea of the inner ear.

 nice flow chart n video on the mechanism of hearing .Thnx meritnation!

cheers!!

steps of making a working model of reflex arc as my project for exhibition

can i have a labelled diagram of vestibular appratus ?

 dear experts , i have some questions here 

1.the hormone which when deficient causes cushings syndrome .

2.give two points of difference between cretenism and myxoedema .

3.can there be dna replication without cell division . comment.

4.enumerate the different types of nerve fibres depending on nature and function .

5 . a person has excessive thirst and production of large amount of urine . the doctor did not advice him to stop taking sugar . name the disese and explain what happens in it .

6.difference between glomerular filtration and ultra filtration .

please i need these answers by tomorrow night .its a request .

Explain the following processes:

(a) Polarisation of the membrane of a nerve fibre

(b) Depolarisation of the membrane of a nerve fibre

(c) Conduction of a nerve impulse along a nerve fibre

(d) Transmission of a nerve impulse across a chemical synapse