College Bio Unit 3

All cells ______

Divide, no living organism can live without cell division

Mitosis

Cell division, provides a continuous supply of replacement cells for growth, injuries, tumors

Prokaryotes divide by ______

Binary fission

Asexual reproduction (in bacteria and archaea)

Occurs by binary fission

Binary fission

A process that replicates DNA and distributes it to 2 identical daughter cells

Eukaryotic cells divide by _____

Mitosis, but can also divide by meiosis

Meiosis

Each mature individual produces sex cells by another form of cell division

DNA replication is linked to _______

Cell division

What phase does DNA replication occur?

S phase

DNA replication

Cells must copy their DNA before they can divide. The entire genome is replicated so that each new cell gets one complete copy of the DNA

In DNA replication ____ strands are copied

Both

Mitosis generates ____

Exact cell copies. At the end of mitosis, two new daughter cells have exactly the same DNA as the parent cell

Interphase

Cell is not dividing, cells are carrying out their normal everyday functions unrelated to cell division

Chromosome

Nucleic acids and proteins, carry genes

Chromatin

Loose genetic material, prior to mitosis

Chromatid

1 of 2 parts that make up a replicated chromosome

Centromere

Attaches 2 sister chromatids, centriole

Centrosome

Organelles that attach microtubioles (anaphase)

Microtubioles

Have centrioles which are an anchor

PMAT

1. Prophase

2. Metaphase

3. Anaphase

4. Telephase

G1

Normal life

S

DNA replication

Checkpoint 2

S and G2, checks if DNA is replicated correctly

Checkpoint 1

Between G1 and S, checks if cell is big enough for division and replication, also if it has the right proteins. This is what is incorrect in cancer cells

If the cell fails at checkpoint 1, what happens?

Resting phase

Cells enter mitosis leaving ______ phase

G2

Mitosis is followed by ______

Cytokinesis

Cytokinesis

The division of the cell itself

C3/M checkpoint

Between metaphase and anaphase, checks that DNA is ready to divide

Mitosis starts with ______-

Prophase (Chromosomes are organizing)

Prophase

Chromsomes condense and spindle forms

Early prophase

Chromosomes condense, centrosomes move to opposite ends of the cell

Late prophase

Nuclear envelope disintegrates, spindle fibers/microtubioles attach

Metaphase

Chromosomes line up at the equator, 46 chromosomes, longest stage after interphase, M checkpoint at end

Mitosis has 46 chromsomes on equator, _____ (2N)

Diploid

Meiosis has 2×23 chromosomes on equator, and _____ chromosomes

Homologous

Anaphase

92 chromosomes, spindle separates the chromatids. Motor proteins help pull microtubules

Telophase

92 chromosomes, chromosomes unwind and spindle dissolves, nuclear envelope reforms, microtubules disappear

Cytokinesis has _____

2×24 chromosomes, 2 cells, splits the cell