Question

chromosome challenge
directions: use the internet to find the type of reproduction and number of chromosomes in the body cells and sex cells of the organisms on the list. if the information does not apply, type n/a for not applicable.

1. what quantitative observation can you make about the numbers in column 2 compared to the numbers in columns 3 & 4?
2. which organisms on the list go through the process of mitosis? how do you know?
3. what can you conclude from column 1 based on the information in the data table?

Explanation:

First, we complete the chromosome table, then answer the questions:

---

Completed Chromosome Table

Organism	Type of Reproduction	Body Cell Chromosome Number	Sex Cell (sperm) Chromosome Number	Sex Cell (egg) Chromosome Number	Fertilized Egg Chromosome Number
Hydra	asexual	32	N/A	N/A	N/A
Cat	sexual	38	19	19	38
Dog	sexual	78	39	39	78
Amoeba (protist)	asexual	50 (typical)	N/A	N/A	N/A
Onion	sexual/asexual	16	8	8	16
Wheat	sexual/asexual	42	21	21	42
Fruit Fly	sexual	8	4	4	8
E. Coli (bacteria)	asexual	1 (circular chromosome)	N/A	N/A	N/A
King Crab	sexual	208	104	104	208
Zebrafish	sexual	52	26	26	52

---

Question 1

Step1: Compare column values

For sexually reproducing organisms, body cell chromosome count = $2 \times$ sex cell chromosome count.

Step2: State quantitative pattern

Column 2 numbers are exactly double Columns 3 & 4 numbers.

Mitosis is cell division for growth/repair, used by all eukaryotic organisms to make body cells. Prokaryotes (E. Coli) use binary fission, not mitosis. All listed eukaryotes use mitosis to produce diploid body cells.

Column 1 shows two reproduction categories: sexual (requires sex cells, fertilization) and asexual (no sex cells, offspring are clones). Organisms use one or both strategies based on their biology.

Answer:

For sexually reproducing organisms, the number of chromosomes in body cells (Column 2) is twice the number of chromosomes in sex cells (Columns 3 & 4).

---

Question 2