Biology in Focus Chp 9

the mitotic phase

During _____ both the contents of the nucleus and the cytoplasm are divided.

interphase

During _____ the cell grows and replicates both its organelles and its chromosomes.

From the end of S-phase in interphase through the end of metaphase in mitosis

During which stages of the cell cycle does a chromosome consist of two identical chromatids?

Metaphase, Anaphase

Identify the stages of mitosis indicated with the red and blue arrows respectively below.

large cells containing many nuclei

In some organisms, such as certain fungi and algae, cells undergo the cell cycle repeatedly without subsequently undergoing cytokinesis. What would result from this?

Cells with more than one nucleus

In the cells of some organisms mitosis occurs without cytokinesis this will result in?

The cells show characteristics of tumor

Researchers began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. what could they conclude right away?

Cleavage furrow formation and cytokinesis

The drug cytochalasin B blocks the function of actin. which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B?

A plant cell in the process of cytokinesis

Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely.

G1

Which is the first and most important checkpoint in the cell cycle where a cell will be caused to exit the cycle if this point is not passed ?

Replication of the DNA

Which of the following does not occur during mitosis?

They remain confined to their original site

Which of the following is true of benign tumors, but not malignant tumors?

fat, testosterone, cigarette smoke, UV light,->all of the above are carcinogens/

Which of these is NOT a carcinogen?

They have been shunted in Go

Why do neurons (nerves cells) and some other specialized cells typically fail to divide once mature?

They have uncoiled to form long, thin strands

Why is it difficult to observe individual chromosomes with a light microscope during interphase?

fat

_____ is a carcinogen that promotes colon cancer