Cell Division and Chromosomes Flashcards
Define mitosis:
A type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
What is the purpose of mitosis?
Mitosis is required for the development of embryos, growth, tissue repair, and asexual reproduction.
How do the daughter cells compare to the parent cells in mitosis?
Two identical daughter cells
Define meisois:
A type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes
What is the point of meiosis?
This process is required to produce egg and sperm cells for sexual reproduction.
How do the daughter cells compare to the parent cells in meiosis?
In contrast, meiosis gives rise to four unique daughter cells, each of which has half the number of chromosomes as the parent cell.
Define crossing over:
Crossing over, as related to genetics and genomics, refers to the exchange of DNA between paired homologous chromosomes (one from each parent) that occurs during the development of egg and sperm cells (meiosis).
Why is crossing over important?
It allows the daughter cells of meiosis to be genetically unique from one another.
Draw a picture of crossing over:
Two different colored chromosomes. One of their chromatids has two different colors, while the other chromatids are normal. (look if up as well)
In what phase of cell division is DNA replicated?
It happens in S Phase.
Why does DNA need to be replicated?
DNA replicates before a cell divides to give a complete set of genetic instructions to each daughter cell.
What is a diploid?
A cell containing two complete sets of chromosomes, one from each parent.
What is a haploid?
Haploid describes a cell that contains a single set of chromosomes. The term haploid can also refer to the number of chromosomes in egg or sperm cells,
How many chromosomes do humans have?
46 total chromosomes. 23 pairs.
How many chromosomes do human sperm and eggs have?
23 chromosomes.
What is fertilization?
During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote.
As a human, we all started as one cell, and all of our cells have the same genetic material, so how can we have so many different types of cells as adults?
To get at the information, a gene must be turned on (expressed) and the information turned into something useful, a protein. Once made, that protein goes out into the cell and performs some set of specific tasks.
Are clones produced by mitosis or meiosis? Explain.
They’re produced by mitosis, as cells produced by mitosis are genetically identical.
What are autosomes?
Any chromosome that isn’t a sex one
What is a karyotype good for?
This test can help identify genetic problems as the cause of a disorder or disease
What are chromosomes?
Chromosomes are threadlike structure that carries DNA along with histone protein.
How do chromosomes relate to DNA?
They’re made from DNA
What are homologous chromosomes?
homologous chromosomes are paired chromosomes. You get one from mom, the other from dad.
What are sister chromatids?
Sister chromatids are two identical copies of the same chromosome formed by DNA replication, attached to each other by a structure called the centromere. During cell division, they are separated from each other, and each daughter cell receives one copy of the chromosome.
