final Flashcards
What are the parts of the cell cycle?
1) Interphase
2) Cell Division
What happens during interphase?
This is where the cells spend the most time and perform their normal function or job: Gap 1, S phase, and Gap 2
Gap 1
Cell growth
S phase
DNA replication
Gap 2
Cell growth and preparation for division
What happens during cell division (m phase)
Mitosis, cytokinesis
What are sister chromatids?
Identical copies of DNA attached together to make a chromosome
Only exist after DNA replication after S phase
What is a centromere
The middle of a replicated chromosome
What is a telomere
The ends of the chromosomes
Prophase
DNA condenses into chromosomes
Centrioles moves to the opposite “poles” of the cells and send out spindle fibers
Nuclear envelope breaks down and nucleolus disappears
Metaphase
All the chromosomes are lined up across the equator (center) of the cell
Spindle fibers attach to the centromeres of the chromosomes
Each sister chromatid is attached to a spindle fiber originating from opposite poles
Anaphase
Sister chromatids break apart and are now called daughter chromosomes
Daughter chromosomes are pulled to opposite poles of the cell by spindle fibers
Spindle fibers that aren’t attached to chromosomes elongate the cell
Telophase
Chromosomes arrive at opposite poles of the cell and begin to decondense
Nuclear envelope begins to reform and spindle fibers break down
What is cytokinesis
Cell splitting
What is meiosis
Cell division that produce daughter cells called gametes
What is the product of meiosis
4 haploid cells (half the chromosomes)
Also a possibility of swapping of genetic material between homologous pairs
Random alignment in meiosis
Chromosomes line up at the equator randomly, meaning that the chromosomes from mom and dad can be mixed up in the gametes
What is the genotype
The genetic makeup of an organism (alleles)
What is the phenotype
An observable trait (visual appearance)
Dominant vs recessive
An allele can be either dominant or recessive
What is a dihybrid cross
Two trait cross
Filled out by determining the gametes of both parents using the foil method
What is incomplete dominance
Neither allele is dominant over the other
Offspring’s appearance is a blend between the phenotypes of the 2 parents
What is codomiance
Neither allele is dominant over the other
Both alleles are expressed at the same time and a mixture is observed
What is multiple allelism
More than 2 alleles possible for a given gene
Blood types
A, B, AB, or O
Two blood types can be dominant in order to make a combination of co-dominant blood types
Universal Receiver
AB
Universal Donor
O
What are sex-linked genes
Genes that are located on the X chromosome
What are sex-linked traits
Recessive traits, meaning that both x chromosomes must have the gene in order for the trait to be expressed
What do pedigrees do
Study how a trait is passed from one generation to the next
What is the structure of DNA
Two antiparallel strands running in opposite directions held together by hydrogen bonds and nucleotides held together by covalent bonds
What are the nucleotides in DNA
5-carbon sugar called deoxyribose
Phosphate group
Nitrogenous base
What is the base pairing
A and T= 2 hydrogen bonds
G and C= 3 hydrogen bonds
What is the history of DNA
1) Rosalind Franklin used a technique call x-ray diffraction
2) Watson and Crick built models of potential DNA structures and were able to determine it was a double helix