Mitosis
True or False? Mitosis occurs during interphase.
False! Interphase is the period in which cells are NOT dividing. Mitosis occurs in the M phase
True or False: Genes can determine how species look and act
True
True or False? Meiosis is used only for sexual reproduction.
True. It occurs in the testes and ovaries
Meiosis brings about genetic variation in two key ways. What are they?
Crossing-over and independent assortment
Who is the father of heredity?
Gregor Mendel
True or False? Mitosis is a form of asexual reproduction.
True
A fertilized human egg has how many chromosomes?
46 (total) 23 (pairs)
The fusion of a sperm and an egg results in a what?
Zygote
What is crossing-over?
The exchange of genetic material between non-sister chromatids during meiosis I
What is the difference between a genotype and a phenotype? Give an example.
Genotype: the alleles an individual receives at fertilization. Example: Aa Phenotype: physical appearance of the individual. Example: Brown eyes.
The M phase takes up what percentage of the cell cycle?
10%
How many chromosomes are in a human sperm cell?
23
True or False? Embryotic growth is a mixture of mitosis and meiosis.
False! Embryotic growth is ONLY mitosis, meiosis is used only to create gametes.
What is independent assortment?
When homologues align at the metaphase plate during metaphase 1. They separate in a random manner and result in random mixing of alleles into gametes.
What is the Law of Segregation?
Each individual has a pair of alleles (factors) that separate during gamete formation.
What occurs during mitosis?
Daughter chromosomes are distributed to two daughter nuclei
Deoxyribonucleic acid AKA DNA
What is the purpose of meiosis?
To produce gametes (sperm and eggs) with half of the genetic complement of the parent cells.
What is the significance of sexual reproduction regarding genetic variation?
Sexual reproduction causes novel genetic recombinations
What are two autosomal RECESSIVE disorders?
Tay-Sachs, Cystic Fibrosis, PKU, Sickle cell anemia
When does mitosis occur?
When an organism grows or replaces damaged cells
Where are genes located?
Meiosis produces what kind of cells?
Haploid
What syndromes can happen if chromosomes do not form or pair correctly?
Down syndrome, Klinefelter syndrome, Turner syndrome
What is one autosomal DOMINANT disorder?
Neurofibromatosis or Huntington's Disease