Meiosis A
What is independent assortment? When does it occur?
Different genes separate independently of each other; anaphase 1
How do prokaryotic cells divide?
binary fission/asexual reproduction
What type of cells does meiosis produce?
What is codominance?
More than one allele is dominant. (EX blood type AB)
The offspring from the P generation are called the _____ generation. Describe their features.
F1 - all hybrid, all have the dominant trait
What is synapsis, what is crossing over? When does it occur?
The pairing of homologous chromosomes, a segment overlaps and exchanges genetic material, prophase 1
During mitosis, the daughter cells have DNA identical/nonidentical to the parent cell.
Identical
What type of cells undergo meiosis?
germ line; gonads; ovary and testes
What is incomplete dominance?
When the two traits seem to blend. The phenotype is an intermediate
What did Mendel notice about the F 2 generation?
The recessive trait seemed to "reappear."
When do homologous chromosomes separate? When do sister chromatids separate?
Anaphase 1
Anaphase 2
What is the site where DNA replication occurs called?
origin of replication
True/False; Meiosis 2 and mitosis are almost identical
True!
What is pleiotrophy?
When multiple alleles affect the phenotype.
How does the distance between genes affect how they are inherited?
If they are closer to one another, they are more likely to be inherited together
What are sister chromatids? How are they connected?
Copies of DNA; held together at the centromere
What is chromatin?
a mixture of DNA and protein (histone) formed together.
When do homologous chromosomes separate? When do sister chromatids separate?
Anaphase 1 of meiosis 1; anaphase 2 or meiosis 2
What is genotype and phenotype?
Genotype - genetic make up
Phenotype - physical traits
What do the terms heterozgyous, homozygous recessive and homozygous dominant mean?
heterozygous - one dominant and one recessive
homozygous dominant - two dominant
homozygous recessive - two recessive
List the steps of mitosis in order
Prophase, metaphase, anaphase, telophase
When is DNA duplicated prior to meiosis?
What 3 things give rise to genetic variation?
independent assortment, crossing over and synapsis
Describe the following;
Sickle Cell
Tay sachs
Hemophilia
autosomal receissive
Sickle cell causes sickle shaped cells, Tay Sachs is a slow degeneration of nerve/brain cells, hemophilia causes issues with clotting.
If an organism has a diploid number of 60, what is its haploid number?
If an organism has a haploid number of 20, what is its diploid number?
30 (half)
40 (double)