A form of cell divison in which certain cells are set aside to give rise to haploid gamates.
meiosis
________ have the same genes in the same order but may carry differnt alleles.
homologous chromosomes
__________ helps to generate genetic diversity by mixing up parental traits.
crossing over
mitosis has __ daughter cells per cycle.
2
meiosis has __ daughter cells per cycle.
4
The failure of homologous chromosomes to seperate properly during meiosis.
nondisjunction
cell with an extra chromosome.
trisomies
cell with one less chromosome
monosomies
During which stage of meiosis does nondisjunction occur?
anaphase
A Chromosome chart; photograph of chromosomes in meatphase.
karyotype
How are karyotypes used?
detect chromosomal abnormalities
confirm a clinical diagnosis
determine gender
clarify evolutionary relationship
Who was the father of genetics?
Gregor Mendel
Mendel chose to study_______ because...
pea plants
they were easy to cross pollinate
easily distinguishable traits
The transmission of genetic characters from parents to offspring.
heredity
A unit of heredity composed DNA occupying a fixed position on a chromosome.
gene
Alternate form of a gene
alleles
An organism's allele combination
genotype
Physical expression of the genes.
phenotype
Two of the same alleles
ex: TT tt
Homozygous
Two differnt alleles
ex: Tt
Heterozygous
If present, this allele is present.
dominant
Masked by the dominant allele. May be expressed if paried with another recessive.
Recessive
Contains genetic information neccessary to make proteins.
DNA
The basic building block of DNA is...
nucleotide
A nucleotide is composed of three parts:
Deoxyribose
phosphate group
nitrogen base
What are the four nitrogen bases found in DNA?
adenosine
guanie
thymine
cytosine
Who discovered the structure of DNA?
Watson and Crick
How does RNA differ from DNA?
________ base instead of thymine
________ instead of dexoyribose
________ stranded
Involved in the actual buliding of ________.