APBIO- Chpt 12 Cell Division

Overview- Part 2

Warm-Up: List where the 3

checkpoints occur in cell cycle of a cell carrying out

mitosis.

(1) The student will be able to compare and

contrast binary fission and mitosis. (2) The student will be able to list and

describe how some eukaryotes reproduce through mitosis.

(3) The student will be able to identify internal and external factors that regulate cell division.

(4) The student will be able to explain cancer in terms of the cell cycle.

Objectives

Binary fission is similar in function to mitosis. Asexual reproduction is the creation of offspring

from a single parent. Binary fission produces two daughter cells genetically identical to the parent cell. Binary fission occurs in prokaryotes.

Cell Division in Prokaryotes

(1) Compare and contrast

binary fission and mitosis.

Reflection

Environment determines

what form of reproduction is most advantageous. Asexual reproduction is

an advantage in consistently favorable conditions.

Sexual reproduction is an advantage in changing conditions.

Asexual Reproduction

Some eukaryotes reproduce through mitosis.

Budding forms a new organism from a small projection growing on the surface of the parent.

Asexual Reproduction

Fragmentation is the

splitting of the parent into pieces that each grow into a new organism.

Vegetative reproduction forms a new plant from the modification of a stem or underground structure on the parent plant.

Asexual Reproduction

(2) List and describe how some

eukaryotes reproduce through mitosis.

Reflection

Internal and external factors regulate cell

division. External factors include physical and chemical

signals. Growth factors are proteins that stimulate cell

division. Most mammal cells form a single layer in a

culture dish and stop dividing once they touch other cells.

Regulation of the Cell Cycle

Two of the most important internal factors are kinases

and cyclins.

External factors trigger internal factors, which affect the cell cycle.

Regulation of the Cell Cycle

Apoptosis is programmed cell death.

a normal feature of healthy organisms caused by a cell’s production of self-destructive enzymes occurs in

developmentof infants

Regulation of the Cell Cycle

(3) Identify internal and

external factors that regulate cell division.

Reflection

Cell division is uncontrolled in cancer.

Cancer cells form disorganized clumps called tumors.

Benign tumors remain clustered and can be removed.

Malignant tumors metastasize, or break away, and can form more tumors.

Regulation of the Cell Cycle

Cancer cells do not carry out necessary

functions. Cancer cells come from normal cells with

damage to genes involved in cell-cycle regulation.

Regulation of the Cell Cycle

Carcinogens are substances known to promote

cancer. Standard cancer treatments typically kill both

cancerous and healthy cells.

Regulation of the Cell Cycle

CANCER

In this quick virtual lab you will compare normal cells with cancerous cells and observe the differences between them.

PURPOSE Students will observe and compare normal cells

and cancerous cells. PROBLEM

How do normal and cancerous cells compare? MATERIALS

Computer images to include: slides of normal cells and slides of cancerous cells

Mini Virtual Lab

PROCEDURE

1. Examine slides of normal cells under the microscope using virtual computer images. Draw and describe your observations.

2. Repeat step 1 with virtual computer slides of cancer cells.

Mini Virtual Lab

NORMAL HUMAN SKIN CELLS

Human skin cells can provide

stem-cell-like properties.

Skin Cells- Another Use

HUMAN SKIN CANCER CELLS

ANALYZE & CONCLUDE

Compare. How does the structure of the normal cells compare with the structure of the cancerous cells for each of the slides you viewed?

Infer. Cancer cells not only appear different from normal cells but they also divide more rapidly. Why do you think chemotherapy, a common treatment for cancer, results in the loss of hair?

Mini Virtual Lab

(4) Explain cancer in terms

of the cell cycle.

Reflection