Vocabulary
what do we call chromosomes with the same traits that "pair up" next to each other during Meiosis?
homologous chromosomes
Draw a diagram of Prophase.
Includes:
- chromatin condensed to chromosomes (X)
- nuclear envelope breaking down
- centrioles duplicated, spindle fibers forming
True or False?
Mitosis produces ALL cells found within your body.
False!
Reproductive Cells (egg & sperm) are produced through Meiosis, not Mitosis.
Draw a diagram of Anaphase I.
Includes:
- one cell, starting to form an oval
- tetrads breaking apart
- chromosomes being pulled to opposite ends of the cell by spindle fibers
This process produces IDENTICAL cells (daughter cells are exact copies of parent cells)
Mitosis
What is it called when two homologous chromosomes "pair up" next to each other in Meiosis?
a tetrad
What is missing from the diagram for Metaphase?
spindle fibers - should be attached to chromosomes from centrioles on each side
True or False?
Because Meiosis splits up DNA from two parents, it helps increase genetic diversity.
True!
What is missing from the diagram for Telophase II?
The cleavage furrow! (lol)
The cell should be "pinching in," or beginning to narrow so it can split into two, in the middle.
This process produces the cells that make up your body (hair, skin, bones, organs, etc.)
Mitosis
What is the final step in the Cell Cycle that takes place after Telophase called?
Cytokinesis
Draw a diagram of Telophase.
Includes:
- two cells, still connected in the middle
- split chromosomes within each cell
- nuclear envelope starting to re-form
True or false?
Mitosis and Meiosis both produce DIPLOID (2N) cells.
False!
Mitosis produces DIPLOID cells, and Meiosis produces HAPLOID cells.
Draw a diagram of Metaphase II.
Includes:
- two separated cells
- X's down the middle in line, not in pairs
- spindle fibers attached to sister chromatids
This process produces reproductive cells (sperm & egg cells) that are different from each other
Meiosis
What is the swapping of genetic information between chromosomes in a tetrad called?
crossing over
Look carefully at the drawing of Anaphase. What is WRONG with this diagram?
Chromosomes are not split apart; they should be half an X, not a whole X
True or False?
"Crossing over" during meiosis leads to evolution.
True!
"crossing over" creates new combinations of genetic information, leading to variation in offspring that may help organisms adapt better to their environment.
Look carefully at the diagram for Prophase II. What is WRONG with this diagram?
There is only one cell - by Prophase II, we should have two cells that have split apart
This process produces daughter cells that are HAPLOID (meaning they contain half the genetic information from the parent cell)
Meiosis
What is the term for variations (changes or differences) in a species that are produced through crossing over in meiosis?
genetic diversity
Draw a diagram of Interphase.
Includes:
- only one cell
- nuclear envelope around chromosomes
- chromatin not condensed into X chromosomes
- one centriole (has not duplicated yet)
True or False?
Humans have 46 pairs of chromosomes.
False!
Humans have 46 INDIVIDUAL chromosomes, but only 23 PAIRS of them.
Draw a diagram of Cytokinesis after Meiosis II is complete. How many cells in total are we going to end up with?
Includes:
- FOUR haploid cells, fully split apart
- nuclear envelopes re-formed
- DNA in the form of chromatin
- one centriole in each cell
Both Mitosis & Meiosis!