Cells

Question 1

What is the nucleus?

Answer 1

This is a double membrane bound organelle which stores DNA ?

Question 2

What is the most prominent feature in a light image?

Answer 2

The nucleus
DNA specific stains make the nucleus visible

ie. dark staining chromatin granules (condensed DNA) will be more visible

Question 3

How is DNA organized in non-dividing cells?

Answer 3

Chromatin

Question 4

What are the two types of chromatin?

Answer 4

Heterochromatin
Euchromatin

Question 5

What is heterochromatin?

Answer 5

This is the condensed form of DNA that stains more darkly

Not actively used

Question 6

What is Euchromatin?

Answer 6

This is loose DNA that is less dense and stains lighter.

This is actively being used by the cells

Question 7

What is the nucleolus?

Answer 7

A small region within the nucleus involved in rRNA synthesis.

Question 8

Nucleoplasm

Answer 8

The remaining portion of the nucleus (not DNA, not nucleolus)

Question 9

What is the nuclear envelope?

Answer 9

This is the double plasma membrane structure of the nucleus with nuclear pores that transport of molecules.

Outside edge contracts the RER

Question 10

What is the cytoskeleton of the cell?

Answer 10

An internal scaffold made of protein filaments to help maintain cell shape and allow for movement within and of the overall cell.

Often too small to see via light microscopy

Can be observed when cells have a lot.

Question 11

What are Microfilaments?

Answer 11

Thin filaments composed of actin

In many cell types (muscle cells)

Involved in pinching cells apart during cell division. (Cleavage furrow