Chromosomes
What is the name of the region that holds two identical sister chromatids together?
Centromere
What type of reproduction involves only one parent and does not require fertilization?
Asexual reproduction
What is the main purpose of therapeutic cloning?
To produce stem cells that could potentially be used to repair or replace damaged tissues
What is the main purpose of mitosis
To produce two genetically identical daughter cells for growth and repair
How many cells are produced at the end of meiosis?
Four haploid cells
A human body cell contains 46 chromosomes. How many chromosomes and sister chromatids would be present after DNA replication but before mitosis begins?
46 chromosomes and 92 sister chromatids
What is the name of the process where a new organism grows off the body of its parent, like a hydra?
Budding
What type of cells are produced through therapeutic cloning that can develop into different types of specialized cells?
Stem cells
During which stage do chromosomes line up along the middle of the cell?
Metaphase
Put the stages of Meiosis I in the correct order:
A. Anaphase I
B. Prophase I
C. Metaphase I
D. Telophase I
B → C → A → D
Why do you end up with 46 chromosomes at the end of mitosis and only 23 chromosomes at the end of meiosis?
Mitosis produces 2 identical daughter cells and goes through one division and meiosis produces 4 unique haploid cells and goes through two divisions rather than one
What type of asexual reproduction occurs when one cell divides into two identical daughter cells, like bacteria?
Binary Fission
In therapeutic cloning, whose DNA is used to create the cloned embryo?
The DNA from the body cell (somatic cell) donor
A cell completes mitosis, but cytokinesis does not happen. Describe what the resulting cell would look like and explain what went wrong
It would be one cell with two nuclei. The nucleus divided, but the cytoplasm did not split into two separate daughter cells
Two siblings have the same biological parents but look different from each other. Explain how meiosis contributes to these differences.
Crossing over creates genetically different gametes
What is the difference between a chromosome and a chromatid?
A chromosome is a DNA structure. After DNA replication, a duplicated chromosome consists of two identical sister chromatids joined at a centromere
A farmer wants to grow 100 strawberry plants that have the same desirable characteristics as one parent plant. Explain which type of reproduction would be best and why.
Vegetative reproduction using runners. It produces genetically identical offspring quickly without seeds or fertilization.
What is the name of the technique used to create Dolly the sheep?
Somatic cell nuclear transfer (SCNT)
A student observes two daughter cells after mitosis. One cell has 46 chromosomes, while the other has 45. What might have gone wrong during mitosis?
The chromosomes may not have separated properly during anaphase. This is called nondisjunction and can result in daughter cells with different chromosome numbers
Why are fraternal twins genetically different even though they develop during the same pregnancy?
They come from two different eggs fertilized by two different sperm, each with unique genetic information.
What does DNA stand for?
Deoxyribonucleic Acid
A population of bacteria reproduces through binary fission. A sudden environmental change occurs, and most bacteria cannot survive. Why might a population that reproduces sexually have an advantage in this situation?
Sexual reproduction creates more genetic variation, increasing the likelihood that some individuals have traits that help them survive the environmental change.
What is the difference between therapeutic cloning and reproductive cloning?
Therapeutic cloning The embryo is created in a lab using SCNT to harvest stem cells, to grown into specialized cells or tissues to treat diseases or injuries rather than being implanted into a womb
A cell has 8 chromosomes before DNA replication. Explain how many chromosomes and chromatids it has:
1. Before DNA replication.
2. After DNA replication.
1. 8 chromosomes and 8 chromatids
2. 8 chromosomes and 16 sister chromatids
A species has 24 chromosomes in each of its body cells.
1. How many chromosomes will each cell have after Meiosis I?
2. How many chromosomes will each cell have after Meiosis II?
1. 12 chromosomes
2. 12 chromosomes