Cell: The Unit of Life

Chromosomes in a bacterial cell can be 1–3 in number and

1. are always circular
2. are always linear
3. can be either circular or linear, but never both within the same cell
4. can be circular as well as linear within the same cell.

In bacteria, plasmid is

1. extra chromosomal material
2. main DNA
3. non functional DNA
4. repetitive gene.

Ribosomes are produced in:

1. Mitochondria
2. Golgi body
3. Nucleolus
4. Cytoplasm

In fluid mosaic model of plasma membrane

1. Phospholipids form a bimolecular layer in middle part
2. Upper layer is non-polar and hydrophilic
3. Proteins form a middle layer
4. Polar layer is hydrophobic

Difference in gram positive and gram negative bacteria is due to

1. cell wall
2. cell membrane
3. ribosome
4. cytoplasm

Element necessary for the middle lamella is

1. K
2. Cu
3. Ca
4. Zn

Microtubules are absent in:

1. Spindle fibres
2. Mitochondria
3. Centriole
4. Flagella

Spindle fibres unite with which structure of chromosomes?

1. Chromocentre
2. Chromomere
3. Kinetochore
4. Centriole

Lysosome contains:

1. Reductive enzymes
2. Oxidative enzymes
3. Anabolic enzymes
4. Hydrolytic enzymes

Which of the following ribosomes are engaged in protein synthesis in animal cell?

1. Ribosomes of only nucleolus and cytosol
2. Ribosomes which occur on nuclear membrane and E.R.
3. Ribosomes of only mitochondria and cytosol
4. Ribosomes of only cytosol