what kind of organisms do binary fission? What are the three steps of binary fissions?
prokaryotes; 1)Duplication of chromosomes and separate of the copies 2) continued elongation of cell 3) Division into two daughter cells
Explain s phase
an unduplicated chromosome, DNA replicated in S phase, making it a bond of two sister chromatids with a centromere in the middle
what are the benefits of sexual reproduction
1. prevents mutation accumulation
2. increase variation by creating novel genotypes
whos the father of genetics
Gregor Mendel
on a pedigree, male carriers for hemophilia have a half filled in square to demonstrate t/f
false - men cant be carriers
what do both mitosis and meiosis have in common?
Both forms of cell division are accompanied by cytokinesis
what are the phases of mitosis
interphase, prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis
what are the costs of sexual reproduction
1. costs of meiosis
2. Costly/dangerous
3. Not Always successful
how did mendel cross breed the pea plants
1. Removal of stamens
2. Transfer of pollen
3. Carpel matures into pea pod
4. seeds from pod planted
if a trait is dominant, it means its common t/f
false
How does DNA make chromosomes
DNA wraps around nucleosomes and histones forming a chromatin fiber which compacts into a chromosome
Internal - cell cycle control molecules, checkpoints
External - environmental conditions, signaling molecules
most chromosomal syndromes are lethal. t/f
true
why is it important to know the genotype along with the phenotype
because although a phenotype might show outer appearance we wouldnt be able to tell if someone is a carrier (heterozygous) or homozygous
Human hypercholesterolemia is an example of
incomplete dominance
How many autosomes does the human body have
22 pairs
What are the two cancerous defects?
1. Defects that make the proteins required for cell growth active when they should not be
2. Defects that prevent tumor suppressor genes from shutting down the cell cycle
explain law of independent assortment
Describes how different genes independently separate from each other when reproductive cells are developing; Alleles of at least two genes are sorted into gametes / independently of one another
where would you find alleles on chromosomes
loci
sickle cell anemia is an example of
codominance
what phase in the whole cell cycle is the longest
s phase
what type of ploid cell am i talking about? We get one pair from our biological mother and one pair from our biological father
diploid
what two phases of meiosis are essential for crossing over
late prophase - chiasma
metaphase I- independent assortment
what is the physical association of two or more
genes found on the same chromosome
linkage
what is the difference between pleiotropy and polygenic genetic interactions
pleiotropy has one gene that codes for many traits while polygenetic is many genes that code for one trait