LS 2-7 Final

heredity

The passing of genetic information from parents to offspring

trait

A specific characteristic that can vary from one individual to another

ie. eye color, hair color, height

gene

Basic unit of heredity, a segment of DNA that contains instructions for building proteins that form an organism's traits

allele

A version of a gene, can determine a specific trait, represented as a individual letter

Ie. white fur or no fur

Dominant allele

An allele whose trait always shows up in the organism when the allele is present. Represented with UPPERCASE letters.

Ie. the white fur/white bead

Recessive allele

An allele that is hidden whenever the dominant allele is present. Represented with lowercase letters. (ie. the no fur trait/red bead)

Genotype

The combination of alleles inherited for a particular gene, written as a pair of letters Example: WW, for two white fur/beads

BB, for two blue flower alleles

Phenotype

The physical expression (observable trait) due to inherited alleles. Example: Blue flower color

Homozygous

To have two of the same alleles for a gene

Heterozygous

To have two different alleles for a gene

Punnett Squares

genetic diagrams that are used to work out the probability (likelihood) of possible offspring genotypes.

Purebred

another name for a homozygous trait in an organism that has two of the SAME alleles for a gene (XX or xx)

hybrid

Another name for a heterozygous trait in an organism that has two different alleles for a trait

codominance

A condition in which both alleles for a gene are dominant and are fully expressed

square

what shape represents males on a pedigree?

pedigree

A diagram that shows the occurrence of a genetic trait in several generations of a family.

circle

what shape represents females on a pedigree?

a horizontal line connecting a male and female

what represents a marriage/union on a pedigree?

a vertical line connected to a marriage/union

what represents children on a pedigree?

shaded symbols

what represents individuals that have a specific trait we're analyzing on a pedigree?

reproduction

the biological process of creating offspring.

asexual reproduction

occurs when one parent creates a genetically exact copy of itself known as a clone.

sexual reproduction

occurs when two parents mix genes in order to produce unique offspring.

mitosis

a process of cell division in which a single cell divides to form two identical cells. All chromosomes (genes) are identical. an example of asexual reproduction.

meiosis

a type of cell division where two parents cells divide to create four genetically unique daughter cells that each have half of the chromosomes (genes) of the parent cells. an example of sexual reproduction.

only need one parent, produces offspring more quickly, can produce a lot of offspring

what are some advantages of asexual reproduction?

no genetic variation, bad characteristics can be passed on, difficult for organisms to adapt

what are some disadvantages of asexual reproduction?

budding, mitosis, fragmentation, spores, propagation

what are some examples of asexual reproduction?

smaller population produced, happens more slowly

what are some disadvantages of sexual reproduction?

high genetic variation, organisms are better able to adapt

what are some advantages of sexual reproduction?

carrier

Another name for a heterozygous or hybrid trait, a person whose "carries" the trait but doesn't express/show it

cell

smallest part of living things, the basic unit of structure and function in living things

DNA

A complex molecule containing genetic information