Genetics Test Flashcards
trait
characteristic of an organism
genetics
study of genes and heredity
alleles
one of two or more alternate forms of a gene
heredity
process of passing traits from parent to children
purebred
homozygous - genes that are alike for a particular trait
dominant
a dominant gene will show up no matter what other genes are present. Capital letter.
recessive
A recessive gene will only show up if it is paired with another recessive gene. lowercase letter
Punnett Square
the tool used to determine the outcomes of genetic crosses
phenotype
describes the physical appearance of an organism
genotype
used to describe the genes of an organism
homozygous
genotype where the genes are the same
heterozygous
genotype where one gene is dominant and one is recessive
selective breeding
choosing parents with particular characteristics to breed together and produce offspring with more desirable characteristics.
How do we distinguish a dominant trait from a recessive trait?
Capital for dominant and lowercase for recessive
Difference between allele and gene
a gene is a code for a specific trait; alleles are variations of a gene
Difference between heterozygous and homozygous?
Homozygous made with two of the same alleles. Heterozygous is made with two different alleles.
Examples of homozygous and hetereozygous.
Pea Plant: Yellow - Y Green - y
Homozygous: YY or yy
Heterozygous: Yy
genotype vs phenotype
genotype is an organism’s specific genetic code; Yy
phenotype is the physical expression of a characteristic: Yellow
Blood Types
A, B, AB, O
Chromosomes affected by sex-linked disorders
X or Y
recessive disorders
sickle cell, Tay-Sacs Disorder, Cystic Fibrosis
sex-linked disorders
Hemophilia
mitosis
division of somatic (body) cells
meiosis
sexual reproduction that produces four new sex cells or gamete each with half the usual number of chromosomes.
mitosis stages
Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis
meiosis stages
Meiosis I - Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis
Meiosis II - Interphase II, Prophase II, Metaphase II, Anaphase II, Telophase II, Cytokinesis II
compare meiosis and mitosis
Same stages in each process for cell division
contrast meiosis and mitosis
cell division once in mitosis and twice in meiosis; mitosis produces cell with same number of chromosomes and meiosis produces cell with half the number of chromosomes. Mitosis - 4 phases, Meiosis - 8 phases; Mitosis - 2 daughter cells and meiosis 4 daughter cells; Mitosis - asexual reproduction and meiosis - sexual reproduction]
