During DNA replication in prokaryotes DNA is anchored to

• chromosome

• mesosome

• nucleolus

• ribosome

The mineral present in cell wall is

• Na

• Ca

• K

• Mg

263.

Which organelle is present in higher number in secretory cells?

• Dictyosome

• ER

• Lysosome

• Vacuole

Cell membrane in animals is composed mainly of the molecule of

• lipids

• proteins

• lipids and proteins

• carbohydrates

A student wishes to study the cell structure under a light microscope having 10X eyepiece and 45X objective. He should illuminate the object by which one of the following colours of light so as to get the best possible resolution?

• Yellow

• Green

• Blue

• Red

Which one is single membrane cell organelle

• Endoplasmic reticulam

• Mitochondria

• Lysosomes

• Chloroplast

Centromere is required for

• transcription

• crossing over

• cytoplasmic cleavage

• movement of chromosomes towards poles

Protein synthesis in an animal cell occurs

• only on the ribosomes present in cytosol

• on ribosomes present in cytoplasm as well as in mitochondria

• only on ribosomes attached to the nuclear envelope and endoplasmic reticulum

• on ribosomes present in the nucleolus as well as in cytoplasm

The main organelle involved in modification and routing of newly synthesized proteins to their destinations is

• mitochondria

• endoplasmic reticulum

• lysosome

• chloroplast

Cell theory was propounded in 1838-39 by

• Schleiden

• Schwann

• Schleiden and Schwann

• Virchow