• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/35

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

35 Cards in this Set

  • Front
  • Back
Chromosomes
- composed of DNA & proteins
- each chromosome consists of hundreds of structural & functional subunits called genes
- A gene is a sequence of nucleotides in a DNA molecule that contains coded info for making a specific protein (usually an enzyme)
- enzymes in particular determine an individual's observable physical traits of characteristics
Gregor Mendel
- 1822
- father of genetics
- experiments with heredity (passage of traits from one generation to the next)
Common Garden Pea
- mendel used it because:
- its commercially available
- easy to cultivate
- grows rapidly
True Breeding
- some pea plants, if allowed to self-pollinate will consistently produce the same characteristics over and over again.
- ex: if mendel allowed purple plants to self pollinate, they would produce nothing but purple plants (true breeding)
Chromosomes
- composed of DNA & proteins
- each chromosome consists of hundreds of structural & functional subunits called genes
- A gene is a sequence of nucleotides in a DNA molecule that contains coded info for making a specific protein (usually an enzyme)
- enzymes in particular determine an individual's observable physical traits of characteristics
Gregor Mendel
- 1822
- father of genetics
- experiments with heredity (passage of traits from one generation to the next)
Common Garden Pea
- mendel used it because:
- its commercially available
- easy to cultivate
- grows rapidly
True Breeding
- some pea plants, if allowed to self-pollinate will consistently produce the same characteristics over and over again.
- ex: if mendel allowed purple plants to self pollinate, they would produce nothing but purple plants (true breeding)
P Generation
- original parent generation
F1 Generation
- the 1st generation of offpspring ["filial"<??(L)=son/daughter]
Dominant Trait
the characteristic that appears in the F1 generation
F2 Generation
- the 2nd generation of offspring (resulting from a cross between 2 members of the F1 generation)
Recessive Trait
- the trait that disappears in the F1 generation, but reappears in the F2 generation
Alleles
- different (alternative) molecular forms of a gene that occupy the same locus (position ) on a a pair of homologous chromosomes.
- all alleles are genes, but not all genes are alleles
Principle of Segregation
- every individual carries a pair of alleles for each trait & members of the pair segregate during the formation of gametes (sex cells)
- meiosis
- mendel's 1st law
Homozygous
- refers to a pair of identical alleles
- both will be expressed
- if 2 alleles are identical, both traits will be expressed
Heterozygous
- refers to a pair of non-identical alleles
- one allele may be dominant over the other & the organism will appear as if it only had the dominant allele
Phenotype
- the outward appearance of a trait; an individual's observable traits
- ex: purple flowered plant= phenotype
Genotype
- the actual genetic makeup of a trait
- the genes present in an individual
- each allele still exists independently & as a discrete unit, even though it may not be expressed in the phenotype
Punnett Square
- predicts the possible genotypes (gene make up) and phenotypes (outward appearance) of the offspring and their expected ratios.
Test Cross
- a cross between 2 individuals-one with a dominant phenotype (the unknown) for a given trait, & one that is homozygous recessive for a given trait
Monohybrid Cross
- one that involves the transmission of only 1 trait or characteristic>through the alleles
- F2 3:1 ratio
Dihybrid Cross
- one that involves the transmission of 2 traits (or characteristics) simultaneously
- F2 9:3:3:1 ratio
Principle of Independent Assortment
- states that members of each pair of alleles are distributed independently when gametes (sex cells) are formed
- also known as mendel's 2nd law
- a lot of exceptations
gene interactions- the effects of genes are influenced by:
- their alleles (incomplete dominance & co-dominance) and their environment
incomplete dominance
- the heterozygous individuals (have non-identical alleles) of the F1 generation show effects of both alleles
- the F1 offspring have a phenotype different from both parents
- the F2 phenotypic ratio is 1:2:1 (rather than the 3:1 as occurs in complete dominance)
Codominance
- both alleles are expressed simultaneously & so are unmodified in the heterozygous individual .
- ex: ABO blood group antigens (recognition markers found on the surface of RBCs)
- 3 alleles: IA, IB,i
multiple alleles
-the presence of 3 or more alleles in a population for a single trait.
- ex: ABO blood groups
Environment
- the phenotype (outward appearance) of any organism is the result of interaction between its genes and the environment
- ex: a seedling & the sun, temperature & the arctic fox.
- the genes of the fox are the same, just the phenotype has changed
- ex: seed has genetic capacity to be green in photosynthesis, but if kept in dark, won't turn green
Mutation
- any relative stable, heritable change in the genetic material. at the molecular level, a mutation is a change of 1 to several bases in the nucleotide (4) sequence.
- the rate at which any one gene undergoes mutation is very low (the rate of spontaneous mutations average 1/million replications)
- vast majority of mutations are deleterious (harmful)
- when 2 heterozygous parents with same deleterious recessive trait mate, they have higher chance of getting child with the gene.
Mutant
- any organism exhibiting changes or mutations
Mutagen
- any agent producing mutations. ex: something radioactive
Lethal
- an allele whose pheotype, when expressed results in the death of the organism
Pleiotrophy
- the capacity of a gene to effect a number of different phenotypic characteristics
- ex: gene for sickle cell anemia
Polygenic Inheritance
- refers to the fact that a single trait is often affected by many genes
- ex: human eye color, skin color, height because your parents give you the genes they have