Unit 3 Notes

Multiple Choice

Why is it important for cells to organize their DNA into chromosomes before cell division?

• To help keep genetic information organized

• To make the cell larger

• To increase the number of chromosomes

• To speed up metabolism

Multiple Choice

What is the function of the centromere in a chromosome?

• It holds sister chromatids together

• It replicates DNA

• It produces proteins

• It breaks down chromosomes

Open Ended

Why do you think your body needs to constantly produce new cells? List at least 3 reasons.

Fill in the Blanks

Cells divide for two main reasons: growth and to replace

or old cells.

Multiple Select

Which of the following are main stages of the cell cycle?

• Interphase

• Mitosis

• Cytokinesis

• Replication

Multiple Choice

Which phase of the cell cycle involves the cell growing in size, making new enzymes and organelles, and preparing for DNA replication?

• G1 phase

• S phase

• G2 phase

• M phase

Multiple Choice

During which phase of the cell cycle does DNA replication occur, resulting in two identical sets of DNA?

• G1 phase

• S phase

• G2 phase

• M phase

Multiple Select

Which of the following occur(s) during the M phase of the cell cycle?

• DNA forms into chromosomes

• Cell divides DNA and parts into two identical daughter cells

• Division of cytoplasm to form two identical daughter cells

• DNA replication

Fill in the Blanks

Fill in the blank: The phase in which the cell is not dividing or preparing to divide is called the

phase.

Open Ended

What could happen if the DNA doesn’t copy accurately during the S phase?

Multiple Choice

Which of the following correctly matches the phase of the cell cycle with its main event?

• G1 Phase - DNA replication

• S Phase - Cell prepares for division

• Mitosis - Nucleus divides into two identical nuclei

• Cytokinesis - Cell grows and carries out normal functions

Fill in the Blanks

Fill in the blank: If a cell does not meet the requirements at a checkpoint, it will enter

phase or undergo apoptosis.

Multiple Select

Which of the following are benefits of apoptosis for the body?

• Replaces old cells

• Strengthens immune system

• Gets rid of damaged cells

• Causes uncontrolled cell growth

Multiple Select

What are possible consequences if cell cycle checkpoints stop working?

• Uncontrolled cell growth

• Cell death

• Failure to fix DNA errors

• Increased cell differentiation

Multiple Select

Which of the following are considered carcinogens that can cause cancer?

• Sun exposure

• Tobacco use

• Viruses

• Exercise

Multiple Choice

Which of the following best describes cancer?

• Uncontrolled cell growth that causes tumors

• A type of virus that infects cells

• A normal process of cell division

• A harmless change in DNA

Fill in the Blanks

DNA is in a double

shape.

Labeling

Using the labels, identify the parts of a DNA molecule.

Drag labels to their correct position on the image

Base pair

Phosphate

Nitrogen Base

Nucleotide

Hydrogen bond

Deoxyribose

Multiple Choice

Which of the following is NOT a part of a nucleotide?

• Phosphate group

• Deoxyribose sugar

• Nitrogen base

• Amino acid

Multiple Choice

Cyosine matches with _

• Guanine

• Uracil

• Thymine

Multiple Choice

Adenine matches with _

• Guanine

• Uracil

• Thymine

Multiple Select

Which of the following statements about DNA are correct?

• DNA stores genetic information.

• DNA is composed of nucleotides.

• DNA is a double helix.

• DNA is made up of amino acids.

Multiple Choice

In what phase of the cell cycle does DNA replication take place?

• G1

• S

• G2

• Prophase

Multiple Choice

What is needed for DNA replication to unzip at the hydrogen bonds?

• phosphates

• enzymes

• deoxyribose (sugar)

• hydrogen

Multiple Choice

The process of DNA replication is called semi conservative because it results in

• none of these

• Two DNA molecules.  One original molecule and one with two new strands

• two exact copies with new strands

• two DNA molecules, each with 1 original strand and one new.

Multiple Choice

Contains one new and one old strand

• enzymes

• helicase

• template

• semiconservative