Mitosis and meiosis compared
Grade 9 Science Worksheet - Challenge Me
Circle the best answer.
Ari follows a model animal with 2n = 6. An egg cell and a sperm cell, each made by meiosis, join. How many chromosomes does the joined cell have?
- 3 chromosomes
- 12 chromosomes
- 6 chromosomes
- 9 chromosomes
Bo reads the model card for a germ cell line. How many cells exist after step 2?
- 256 cells
- 16 cells
- 12 cells
- 32 cells
Read this first
Use this
Sister chromatids in a model cell (model data), 4 rows. Columns: step, what happens. start, 2n = 6, chromosomes copied, so each has 2 sister chromatids. mitosis, sister chromatids separate and each becomes a chromosome. meiosis I, sister chromatids stay joined and the chromosome pairs separate. meiosis II, sister chromatids separate and each becomes a chromosome.
Esme counts the chromatids in each daughter cell of the model cell, after mitosis and after meiosis I. What are the counts?
- 12 after mitosis and 6 after meiosis I
- 3 after mitosis and 3 after meiosis I
- 6 after mitosis and 3 after meiosis I
- 6 after mitosis and 6 after meiosis I
Lab card (model data)
item reading cell line cells that make sperm cells starting cell 2n = 8 divisions 1 cells made 2 chromosomes in each new cell 8 purpose more cells for the line Jun reads the lab card about a cell line that makes sperm cells. Which choice names the division and gives the reason?
- Meiosis, because 2 cells were made from the sperm-making line
- Meiosis, because the 2 new cells are identical to each other
- Meiosis, because any dividing animal cell in that line uses meiosis
- Mitosis, because germ cells also divide to make more germ cells
Chromosome cards (model, no crossing over, not to scale). Luz compares four sets of daughter cards from a parent with 2n = 4. Which set shows the cells from one complete meiosis?
- Set R: 4 cells, each with the full set of cards
- Set S: 2 cells, each with half the cards
- Set Q: 4 cells, each with half the cards
- Set P: 2 cells, each with the full set of cards
Use this
Notebook, mitosis (model data), 4 rows. Columns: line, what was written. 1, The chromosomes are copied before the cell divides. 2, One division makes 2 new cells. 3, Each new cell has 3 chromosomes, half of the parent's 2n = 6. 4, The new cells match the parent cell.
Milo checks a classmate's notebook about mitosis. Which choice finds the mistake and fixes it?
- Line 3: each new cell should have 6 chromosomes
- Line 2: mitosis should make 4 new cells
- Line 4: the new cells should differ from the parent
- Line 1: the chromosomes should be copied after the division
Use this
Notebook, meiosis (model data), 4 rows. Columns: line, what was written. 1, The chromosomes are copied once, before meiosis begins. 2, Two divisions follow in a row. 3, Four cells are made, each with 4 chromosomes, for 2n = 8. 4, The four cells are identical, because the chromosomes were copied exactly.
Noah checks a classmate's notebook about meiosis. Which choice finds the mistake and fixes it?
- Line 3: each cell should have 8 chromosomes
- Line 2: meiosis has 1 division
- Line 4: the four cells differ from each other
- Line 1: the chromosomes should be copied twice
Notebook, strawberry runner (model data)
line what was written 1 A parent strawberry plant sends out a runner 2 Cells of the runner divide by mitosis 3 A new plant grows at a node and matches the parent 4 The new plant began when an egg cell and a sperm cell joined Pia checks a classmate's notebook about a strawberry runner. Which choice finds the mistake and fixes it?
- Line 4: no cells joined; the plant grew from the parent
- Line 1: a runner is part of the root, not the stem
- Line 2: the runner's cells should divide by meiosis, not mitosis
- Line 3: the new plant should differ from the parent plant
Claim card (model data)
claim reason given Every egg and sperm cell from one animal is identical meiosis copies the chromosomes just once Ren reads the claim card. Which reply gives the right verdict with the right reason?
- Yes: meiosis makes cells that are identical, as mitosis does
- No: meiosis makes 2 cells, which is too few to compare
- Yes: cells from one animal share the same chromosomes
- No: crossing over and random lining up make the cells differ
Tala reads the claim card. Which reply gives the right verdict with the right reason?
- No: body cells use mitosis, which keeps the full number
- Yes: meiosis is how any body cell makes new cells for the body
- No: skin cells use mitosis, which halves the chromosome number
- Yes: meiosis keeps the full number, which a skin cell needs