Biology: The Cell Cycle Test

What limits a cell's size?

The surface area to volume ratio. Also information crisis and traffic problems.

The larger the ratio, the bigger the cell.

What is a chromosome?

A coiled strand of two sister chromatids (identical DNA)

Parts of chromosomes?

Two sister chromatids

They meet in the middle at the centromere

What are chromosomes made of?

DNA and protein

How many chromosomes does a human have in each body cell?

46

What does chromosome start out as and what does it become?

It starts as a big jumble (pasta noodles) of genetic material, called chromatin, but during Prophase it condenses to form chromosomes

Sexual vs. asexual reproduction:

sexual: two cells fuse together to make new (two sets of DNA

asexual: one set of DNA copies itself (one set of DNA)

Order of the cell cycle? What happens in interphase vs M phase?

Interphase

- G1

- G0

- S Phase

- G2 Phase

M Phase

- Mitosis

- Cytokinesis

What happens in G1?

Cell growth

What happens in S Phase?

DNA replicates

What happens in G2?

Cell preps for mitosis

What happens in G0 Phase?

It's a branch off of G1 where cells with problems go and divison is paused dividing. This can be permanent or temporary

What type of cells stay in G0 phase?

Nerve cells. Neurons. Cells that no longer need to divide

What happens in mitosis?

PMAT

What happens in Prophase? 3

Nucleus disappears, chromosomes condense and are visible, spindle fibers form

What happens in Metaphase? M for? 2

Middle.

Chromosomes line up single file down middle of cell. Spindles attach to the centrioles of the chromosones

What happens in Anaphase? A for? 1

Away.

Sister chromatids get pulled apart and moved to the opposite sides of cells by the spindles

What happens in telephase? T for? 3

Two.

Nucleus reforms, spindles fibers disapear, chromosomes start to no longer be visible

What happens in Cytokynesis?

Cytoplasm divides to create to identical daughter cells. Cell membrane pinches and causes clevage until fully apart and now 2 cells

What happens in a plant cell division?

Can't pinch due to cell wall, cell plate forms down middle and will turn into new cell wall for 2 new cells?

Why do cells divide?

To help repair the body and for general maintenance of body tissue. To make new cells to repair damaged ones.

What is a cyclin? When does it show?

A protein that helps regulate the cell cycle. Only when needed at checkpoints

Why would a normal healthy cell stop dividing?

it is touching another cell

What is a cancer cell?

A cell that doesn't respond to regulatory growth signals.

It divides uncontrollably and very frequently.

What causes a cancer cell to occur?

When control over the cell cycle has been lost

How can you tell a cancer cell is present?

When they produce a tumor and begin to displace other cells.

If you cannot catch their is damage, not listening to other cell next to it and keeps growing and pushing

What are the signs of cancer?

Cells dividing too quickly, not listening to checkpoints

What does cancer do?

Not listen to checkpoints, grow uncontrollably

What happens in the G1 Checkpoint? 3

It checks for:

- enough room around for cell division

- Cell has grown enough for enough energy and material for cell function

- no damage to DNA

What happens in the G2 Checkpoint? 3

It checks for:

- checks that DNA is fully replicated

- check for no DNA damage

- have all materials ready for M Phase

What happens in the M Checkpoint? When does it take place?2

Checks for:

- All chromosomes have spindles correctly attached

Metaphase

cell cycle checkpoints

are where the said phase takes place

What is a proto-oncogene? Simple word for it?

Normal genes that play a role in regulating the cell cycle

Green light

What is an example of a proto-oncogene?

Cyclin, go signal for cycle

What is CDK?

Enzyme that is always present but only works when cyclin needed is present. Regulates cell cycle

What do CDK and cyclin do together?

Manage checkpoints

What is a stem cell?

Stem cells are the unspecialized cells from which differentiated cells develop.

What is a Totipotent stem cell?

can develop into any type of cell in the body

(including the cells that make up the extraembryonic membranes and placenta)

What is a Pluripotent stem cell?

cells that are capable of developing into most, but not all, of the body's cell types

What is a Multipotent stem cell?

Can become one cell. limited potential to develop into many different types of differentiated cells

eview how cells differentiate from stem cells into the specialized cells of the body

stem cells start out basic and not specialized and once developed or needed it will become a specialized cell for particular job in the body