Cancer/Asexual Reproduction Review

Cancer and Asexual Reproduction

Regulating the Cell Cycle

Growth factors = special proteins outside of the cell that signal it to divide.

 

Checkpoints = internal factors that act as control points in the cell cycle where a “stop” signal can prevent cellular defects.

If something goes wrong at any of these checkpoints, the cell cycle will be disrupted until cellular conditions are better/DNA repairs are made.

Cell Cycle Checkpoints

How Checkpoints Are Managed

Cyclins = specialized proteins that manage checkpoints

Kinases = specialized enzymes that manage checkpoints

Multiple Choice

A control point in the cell cycle where stop signals can regulate the cell cycle:

• checkpoints

• mutation

• growth factor

• cyclin

Multiple Choice

Special proteins outside of the cell that signal it to divide:

• growth factor

• checkpoint

• tumor suppressor gene

Multiple Choice

Which of the following is NOT a checkpoint in the cell cycle?

• G₁ Checkpoint

• G₂ Checkpoint

• Metaphase Checkpoint

• Cytokinesis Checkpoint

Apoptosis = programmed cell death; occurs when a cell is worn out, damaged, or if an error occurs at a checkpoint. Cancercells do NOT go through this when they are supposed to.

Cancer is uncontrolled cell growth; these cancer cells can then invade healthy tissues.

Carcinogens are things that damage DNA in cells, causing mutations & transforming them into cancer cells

Tumors/Metastasis

A mass of cells that is growing out of control is called a tumor

Metastasis is when cancer cells spread to other areas of the body.

Genes & Cancer

Different genes control the cell cycle

Proto-oncogenes start cell division; tumor suppressor genes stop cell division

When these genes become mutated, they turn into oncogenes which have the potential to cause cancer.

Multiple Choice

Programmed cell death; cancer cells do NOT go through this when they are supposed to:

• apoptosis

• oncogenes

• carcinogens

• oncogenes

Multiple Choice

Things that damage DNA in cells, causing mutations & transforming them into cancer cells:

• carcinogens

• tumor suppressor genes

• cyclins

• checkpoints

Multiple Choice

This is a mutated gene that has the potential to cause cancer.

• oncogene

• proto-oncogene

• tumor suppressor gene

• kinase

Asexual Reproduction

Asexual Reproduction

·      Asexual reproduction uses one parent organism 

·      The offspring is genetically identical to the parent

·      Most types of asexual reproduction take place by the process of mitosis

Binary Fission

a.    Occurs in many unicellular organisms (ex: prokaryotes)

b.    Process: the single-celled organism grows, replicates its DNA, and then splits in half

c.    All bacteria reproduce by binary fission

Multiple Choice

A bacteria splits in half. This is:

• binary fission

• budding

• vegetative propagation

• fragmentation

Budding

a.    Process: a small area of cells attached to the parent organism starts to grow and then detaches when it is a complete organism

b.    Many fungi such as yeast and simple animals such as hydra and sea anemones reproduce by budding

Vegetative Propagation

Some plants reproduce using vegetative propagation

Process: a parent plant might form a creeping stem that roots and forms a new plant

Grasses and strawberry plants often reproduce new plants this way

Even a cutting taken from a leaf or a stem of a plant can sometimes be rooted to form a new plant

Regeneration and Fragmentation

a.    Some simple animals such as sponges, starfish and planaria can regrow their bodies if a piece gets broken off or damaged through a process called regeneration 

b.    If enough genetic material is present in the broken piece, it can also form a new organism through a process called fragmentation

c.    Example: by regeneration, a starfish can regrow an arm that becomes detached; by fragmentation, the broken arm can grow into a completely new starfish.

Multiple Choice

A growth of cells on the side of a hydra falls off and becomes its own organism. This is:

• binary fission

• budding

• vegetative propagation

• fragmentation

Multiple Select

Choose all of the ADVANTAGES of asexual reproduction

• Can make a lot of organisms in a short amount of time

• No energy used to find a mate

• Lots of genetic variation in the population makes the population likely to survive changes