Transport In Plants Question 7

Question: Read the following statements regarding porins and select the correct option given below.

(i) Porins are transport proteins. (ii) Channel proteins are usually gated and are a type of transport protein. (iii) Carrier protein binds the particular solute to be transported. (iv) Particular solute is delivered to the other side of the membrane by carrier proteins.

Options:

A) (i),(ii) and (iii)

B) (i),(iii) and (iv)

C) (i),(ii),(iii)and(iv)

D) (i) and (iv)

Show Answer

Answer:

Correct Answer: C

Solution:

[c] Cell membranes possess certain pores, which are called porin.

These are present in the outer membrane of mitochondria, plastids and in some bacteria.

These large protein pores provide passage for small sized proteins.

These are also called transport proteins, which can be divide into two types; carrier proteins and channel proteins.

Carrier proteins bind to the particular substances, while channel proteins allow movement of an appropriate sized solute to be transported and this in turn is delivered to the outer side of the membrane by carrier proteins.