Biology 40s Exam - Genetics

the process to duplicate body cells into two genetically identical daughter cells

the process to create sex cells or gametes that only have one sit of chromosomes

cell duplication/replication

reduction division

1

2

1 cell -> 2 daughter cells

1 cell -> 4 cells (gametes)

• alternate forms of a particular gene
• the alleles for a trait occupy the same position

the dominant allele will always be expressed

• versions of genes that are less influential
• for a recessive trait to show, one must have two recessive alleles for a specific trait

the gene that an organism has for a specific trait

the observable or expressed traits of an organism

if two alleles display complete dominance, it is not possible to tell the difference between the homozygous dominant individual and the heterozygous individual

having two identical alleles for a given trait

having two different alleles for a given trait

the same as heterzygous

homozygous dominant

sex cells

filial = offspring

• a structure in the cell nucleus that contains dna
• a single piece of dna contains many genes

• the same size, same shape, and have the same gene map
• not necessarily genetically identical

identical copies of chromosome connected by a centromere 

process where two chromosomes pair up and exchange sections of dna

• contains two sets of chromosomes
• one set from each parent

• contains one set of chromosomes 
• gametes

• division of cytoplasm after chromosomes separate
• in plants, new cell wall forms
• in animals, cleavage furrow forms to divide cell

• prophase
• metaphase
• anaphase
• telophase

• mendel experimented with plant heredity by controlling the pollination
• mendel determined that certain factors controlled the characteristics of the plants
• these are genes, he concluded that some are dominant and others are recessive

• law of segregation
• law of independent assortment

each organism has 2 alleles for each trait which separate and only one allele passes to the offspring

each pair of alleles segregates independently of other pairs so that all possible combinations of alleles can occur in gametes

cross between two heterozygous or hybrid parents

a diagram that shows every possible combination of alleles 

• when the genotype is unknown but the individual displays dominant phenotype
• cross with an individual known to have a homozygous recessive genotype 

two heterozygous indiviuals for 2 traits are crossed 

9 3 3 1 rule

• incomplete dominance
• co-dominance
• pleiotropy
• epistasis
• polygenic traits
• lethal genes
• multiple alleles

• the heterozygous condition expresses both alleles for a specific trait
• results in a combined phenotype

two dominant alleles are expressed at the same time without the blending of traits

a single gene can affect another characteristic/phentoype

one gene may interfere with the expression of another gene that is independently inherited

traits that are controlled by more than one pair of alleles

• a mutant form of a gene that results in death if expressed in the phenotype
• can be either dominant or recessive, most are recessive

having 3 or more alleles that affect a particular trait

proteins on the membranes of ever red blood cell

• in the blood plasma
• formed in response to the presence of antigens

• type A: has antigen-A, anti-B antibodies
• type B: has antigen-B, anti-A antibodies
• type AB: has antigen-A & antigen B, no antibodies
• type O: no antigens, anti-A & anti-B antibodies

• type A: I^AI^A or I^Ai
• type B: I^BI^B or I^Bi
• type AB: I^AI^A
• type O: ii

• alleles on sex chromosomes are inherited in predictable patterns
• female - XX (homozygous)
• male - XY (heterozygous)

• involve the gene being on the x-chromosome
• women who have XX have protection of becoming heterozygous, males don't
• males have 1 x-chromosome, they will show the phenotype if they receive the recessive allele

• autosomal dominant
• autosomal recessive
• sex-linked dominant
• sex-linked recessive
• mitochondrial inheritance

• every generation
• family members don't transmit the phenotype
• males and females equally affected

• skips generations
• may transmit phenotype
• males and females equally affected

• every generation
• males pass on to daughters
• females more than males

• skips generation
• daughters may be carriers
• males don't pass on to sons

• inherited from the mother
• mothers are carriers

• monosomy: aneuploidic condition where you have a single copy of a chromosome
• aneuploidy: variation in chromosome number; the gain or loss of a singl chromosome

• turner syndrome
• cri du chat syndrome
• trisomy
• patau syndrome
• edwards syndrome
• down syndrome
• klinefelter's syndrome

women have only one x chromosome

• mew-like cry of affected children due to a malformation of the larynx 
• caused by missing arm of chromosome 5

an abnormal aneuploidic condition where there are three copies instead of two

the embryos that do survive to birth, common abnormalities include - mental & motor challenged

heart abnormalities, kid malformations, and other internal organ disorders

a condition where males have an extra x sex chromosome. xxy

• biological characteristics of both the male and female sexes
• true hermaphrodite =xxxy

the passing on of physical or mental characteristics genetically from one generation to another