Show:
The Cell Cycle
Chromosomes and Vocab
Mitosis
Meiosis
Extra
100
List the phases of the cell cycle in order.
G1, S, G2, mitosis, cytokinesis
100
What is another name for body cells?
Somatic cells
100
List 2 important reasons for mitosis.
Growth / repair of damaged cells / replacement of old tissues
100
1) Another name for sperm and egg cells. 2) What type of cells in our bodies undergo meiosis?
Gametes; germ cells
100
The production of gametes during meiosis and their maturation is known as...
Gametogensis.
200
What are the two steps of M-phase and how are they different?
Mitosis (division of the nucleus/chromosomes) and cytokinesis (division of the cytoplasm and organelles).
200
After S-phase, what shape do chromosomes have? What proteins hold the sister chromatids together?
X-shape; centromere
200
What is the difference between plant cell and animal cell cytokinesis?
Animal cell: cleavage furrow pinches the cell in two. Plant cell: cell plate pinches the cell in two.
200
What does meiosis do to the chromosome number? Because of this, what type of cells are the resulting daughter cells?
It reduces the chromosome number by half. Haploid cells.
200
What types of organisms undergo binary fission? What type of reproduction is it?
Prokaryotes (bacteria). It is asexual reproduction.
300
What happens in "G0"? What type of cells are "stuck" in G0?
The cell "exits" the cell cycle - it will just do its job and will NOT divide. Neurons and heart muscle cells.
300
What is the difference between chromatin and chromosomes, and when do we see each form of DNA?
Chromatin: loosely packed (like spaghetti) DNA seen during interphase. Chromosomes: tightly packed DNA seen during cell division.
300
List the four phases of cell division in order, and briefly describe what happens at each phase.
Prophase: nucleus disappears and spindle fibers appear; metaphase: chromosomes line up on the metaphase plate; anaphase: chromosomes are pulled apart; telophase: two new nuclei form
300
What is synapsis and when does it occur?
Synapsis is the coming together of homologous chromosomes to form tetrads. Occurs during prophase I of meiosis I.
300
Name 3 differences between mitosis and meiosis.
Mitosis: 1 division, makes 2 diploid somatic cells, makes identical cells, keeps the chromosome number the same, important for asexual reproduction Meiosis: 2 divisions, makes 4 haploid daughter cells called gametes, makes genetically unique cells, reduces the chromosome number by half, important for sexual reproduction
400
What happens during S-phase of the cell cycle? Why is it important that S-phase occurs before cell division?
DNA is replicated (copied) during the S-phase. It is important that S-phase occurs before cell division so that each daughter cell can get a complete set of chromosomes.
400
1) Chromosomes that have all the genes for an organism EXCEPT those for organs that determines gender are called... 2) How many pairs of these chromosomes do humans have?
Autosomes. We have 23 pairs.
400
Why is mitosis considered a type of asexual reproduction?
The daughter cells are genetically identical to each other and to the parent cell.
400
Provide a definition for "sexual reproduction".
When two haploid gametes fuse their genetic information together to produce a diploid cell that is genetically unique.
400
In males, what is gametogenesis known as? In females?
Males - spermatogenesis. Females - oogenesis.
500
Throughout the cell cycle their are checkpoints. Name one thing that is "checked" at checkpoint 2? What happens if a cell fails a checkpoint?
To see if the DNA was copied correctly at to see if the cell is the right size. If it fails a checkpoint, the cell will undergo apoptosis (programmed cell death).
500
What are homologous chromosomes?
Chromosomes that have the SAME size & have the SAME genes. We have pairs of them because we get one from mom and one from dad.
500
Mitosis happens in eukaryotic cells only. Prokaryotic cells undergo a similar process to make identical copies of themselves. What is this process called?
Binary fission.
500
What is "crossing over" in meiosis? Why is it important?
During crossing over, a pair of homologous chromosomes switch some genetic information. It is important because it creates more genetic variety in a species (this is why you look similar to, but not identical to, your siblings!)
500
During egg production, only ONE of the cells from meiosis will become a mature egg. Why?
That one cell will receives most of the cytoplasm and organelles. The other cells produced by meiosis become polar bodies, smaller cells that contain just DNA and are eventually broken down.