Which of the following is an example of a haploid cell?

1 2 3 4

0% 0%0%0%

1. Stomach cell2. Brain cell3. Sperm Cell4. Skin cell

How many chromosomes are in your Somatic (body)cells?

1 2 3 4

0% 0%0%0%

1. 232. 323. 644. 46

10

Your somatic (body) cells have how many pairs of homologous chromosomes?

1 2 3 4

0% 0%0%0%

1. 46 pairs2. 23 pairs3. 32 pairs4. 2 pairs

10

Response

Counter

This is a picture of

1 2 3 4

0% 0%0%0%

1. Gamete 2. Chromatin3. Duplicated

chromosome4. Karyotype

10

Response

Counter

Human somatic cells contain _____ pair(s) of sex chromosomes.

A. 22B. 1C. 23D. 46

22 1 23 46

0% 0%0%0%

30

Gametes are _________, meaning they contain one set of chromosomes.

A. DiploidB. HaploidC. TriploidD. Monoploid

Diploid

Haploid

Triploid

Monoploid

0% 0%0%0%

30

If an organism contains 14 chromosomes in each somatic cell, then its gametes each

contain ____ chromosomes.A. 7B. 14C. 21D. 28

7 14 21 28

0% 0%0%0%

30

What is #1 in the picture?

1. Centromere2. Centriole 3. Sister

Chromatid4. Chromatin

1 2 3 4

0% 0%0%0%

10

Response

Counter

What is #2 in the picture?

1. Centromere2. Chromosome3. DNA4. Chromatin

1 2 3 4

0% 0%0%0%

10

Response

Counter

The Cell Cycle

PARTS OF THE CELL CYCLE1. Interphase

• G1• S• G2

2. Mitosis• Prophase• Metaphase• Anaphase• Telophase

3. Cytokinesis

Interphase

90% of cell life cycle cell doing its “everyday job” prepares for duplication if triggered

Characteristics nucleus well-defined DNA loosely

packed in long chromatin fibers

Interphase

G1 – First stage after division Cell increases in size Doubles organelles Cells do everyday job

Interphase

S – DNA synthesis occurs DNA Replication takes place in the nucleus (copies

chromosomes)

G2 – Growth & final preparations for division Prepares for division Proteins that aid in mitosis are made in this stage

Microtubules

Control of the Cell

Apoptosis – Programmed cell death Apoptosis & the cell cycle work together to maintain # of cells in

the body (Homeostasis)

Cell Checkpoints (Each controlled by proteins) G1 – Checks DNA for mutations after G1

If ok the cell cycle goes on, if not… APOPTOSIS! G2 – Check to make sure DNA has been copied correctly

if DNA replicated correctly process moves to mitosis, if not… APOPTOSIS!

M Checkpoint – Checkpoint in mitosis/Checks that chromosomes are

attached to spindle Takes place between metaphase and anaphase Ensures chromosomes have lined up correctly, if not….

APOPTOSIS!

Cancer

Uncontrolled cell growthWhy??Checkpoints in cell cycle break down

Due to mutations in genes that produce proteins that control the checkpoints

Can cause tumors (mass of cells) Malignant tumor – cancerous tumor that may spread to other areas

of the body Benign tumor – non-cancerous tumor Biopsy- sample tissue is taken from tumor to determine if it is

cancerous or not

Metastasis- the spreading of cancer from one part of the body to another

What is the DNA/protein complex called? (Hint: This is DNA when it is unwound)

1. Chromosomes2. Chromatin3. Chromatids4. Centromere

1 2 3 4

14%

0%0%

86%

In which stage of interphase does the cell replicate its DNA?

1. G12. G23. S

1 2 3 4

0% 0%

83%

17%

Programmed cell death is called

1. Mitosis2. Cancer3. Apoptosis4. G0

1 2 3 4

5%0%

76%

19%

Cell growth and final preparation for division occurs at which stage of interphase?

1. G12. S3. G2

1 2 3 4

25%

0%

70%

5%

The Cell Cycle

1. Interphase1. G12. S3. G2

2. Mitosis (PMAT)

3. Cytokinesis

Mitosis – division of the nucleus

4 Parts (PMAT): Prophase, Metaphase, Anaphase, Telophase

Prophase

Chromatin (DNA) condenses into chromosomes

Centrioles move to opposite poles of cell

Microtubules extend from the centrioles to form mitotic spindle Pull apart sister chromatids

Nucleolus disappearsNuclear membrane breaks

downChromosomes attach to

spindle fibers Pro = Prepare

Metaphase

Spindle fibers align chromosomes along the middle of cell Meta = Middle metaphase plate helps to ensure

chromosomes separate properly so each new nucleus

receives only 1 copy of each chromosome

Anaphase

Sister chromatids separate move to opposite poles pulled at centromeres Ana = APART

Telophase

Opposite of prophaseThe chromosomes are at the

poles of the spindle.The spindle fibers

disintegrateThe nuclear membrane re-

forms around the two sets of chromosomes.

Chromosomes uncoil to become chromatin again

Telophase = looks like a Telephone or makes Two nuclei.

Cytokinesis

Cell divides into two identical daughter cells

Plant and animal cells divide the cytoplasm in different ways.

Cytokinesis (Plants)

In plant cells, a new cell wall made of cellulose forms between the 2 new nuclei called the cell plate.

When the new wall joins with the existing side wall, the 2 cells have become separate.

Cytokinesis (Animals)

In animal cells, a ring of protein fibers forms around the cell equator and contacts, pinching the cell in half.