Which of the following characters are found in ribosome?

I. They are composed of $\mathrm{RNA}$ and proteins and are not surrounded by any membrane.

II. The membrane transports a number of ions.

III. They are membrane bound vesicular structures and rich in hydrolytic enzymes.

IV. They help in the synthesis of proteins.

The correct combination is:

Assertion (A): In a vacuole, the concentration of ions and other material will be less than the cytoplasm.

Reason (R): Tonoplast facilitates the transport of ions and other material against concentration to the vacuole. 

The correct option among the following is:

Fill up the blanks with suitable words, respectively. 

Each chromosome has a ____ or _____ on the sides, disc shaped structure is called _____. The _____ chromosome has two equal arms, ____ chromosome has one shorter and one long arm. _____ chromosome has no second arm. The secondary constriction develop small fragment called ______

A) metacentric
B) telocentric
C) centromere
D) primary constriction 

E) submetacentric
F) satellite
G) kinetochore

The correct match is: