Gen BIO 1 Test 3

Genotype

The genetic makeup of a cell or organism (Allele- Hh or Gg or HHGgKk these would be the genotype)

Phenotype

An individuals observable characteristics (height, eye color, hair color)

Genetic Variation

the genetic difference that exist among individuals in a population at a particular point in time.

Homozygous

An individual is homozygous when both alleles are the same. (ie HH or GG or HHGGKK)

Heterozygous

An individual is heterozygous when the alleles are different. (ie Hh or Gg or HhGhKk)

Alleles

A particular form of a gene

Segregation of Alleles

the separation of allele pairs (different traits of the same gene) during meiosis so that they can transfer specifically to separate gametes.

Traits

a specific characteristic of an individual

Autosomal Inheritance

The patterns of in heritance of any genes not on a sex chromosome. These are the standard patterns of inheritance.

Model organism

A species that is used for research because it is practical to work with and the conclusions drawn can be applied to many other species.

Hybridization

Combining two different varieties(Mendel did this with pea plants that different in phenotype for one or more trait.

True breeding(pure line)

These lines are homozygous for a trait. (ie HH or GG or KK)

Dominate Trait

An inherited characteristic that appears in an offspring if it is contributed from a parent through a dominant allele.(ie if you receive H from dad h from mom you will phenotypically present H)

Punnett Square

A tool that helps to show all possible allelic combinations of gametes in a cross of parents with known genotypes

Principals of Segregation

Individuals inherit two copies of each gene one from mom and one from dad and when individual form reproductive cells the two copies equally separate in the eggs and sperm (monohybrid cross) .

Principals of independent assortment.

The two copies of each gene segregate into gametes independently of the two copies of another gene (dihybrid cross).

x-linked traits

off spring has a sex-dependent inheritance patterns

Wild Type

Common Phenotype found in individuals

Mutant

Individuals with an unusual phenotype due to mutations.

Pedigree

shows relationships between family members and indicates which individuals have certain genetic pathogenic variants, traits, and diseases.

Carrier

Some who present the Dominate phenotype of a trait but carries the recessive allele, making the heterozygous. Denoted by a half shaded box in a pedigree

hemizygous

Describes an individual who has only one member of Chromosome pair or chromosome segment rather than the usual two. Hemizygosity is often used to describe X-linked genes in males who have only one X chromosome.

Population

All the individuals of a species that live and reproduce in a certain place at the same time

Population ecology

the study of how and why the number of individuals in a population changes over time and space

Population Size

Total number of all individuals of all ages present in a population

Range

geographic distribution of a population

Abiotic factors

Characteristics of the physical environment (ie temperature, altitude)

Biotic factor

Due to the presences if other species( competition, food)

Population density

the number of individuals per unit area

Uniform population density

Negative interaction occur among individuals that space them out individually

Random population density

the position of each individual in independent of the others

Clumped Population Density

The quality of the habitat is patch or the organisms are social

Age Structure/Class

number of individuals of each age

Survivorship

Number of individuals of each age likely to survive to the following year

Age Specific fecundity

Avg number of female offspring produced by a female of each age

Generation Time

Avg time between a mothers first offspring and the first off spring of her daughter

Type 1 Survivorship Curve

Survivor ship is high at young age and drops quickly with old age (Humans)

Type 2 Survivorship Curve

Individuals have a similar chance of dying each year of there life (Birds)

Type 3 Survivorship Curve

High mortality at young age and high survivorship once adulthood is reached ( insects, plants)

Life History

This describes how an individual allocates resources to grow, reproduce, and do activates, structures related to survival.

High fecundity

Species that grow quick, reach sexual maturity at young age , and produce many seeds/offspring. "live fast die young"

High Survivorship

Grow slow, invest resources in trait that reduce damage from enemies and increase their own ability to compete in their environment

Per- capita rate of increase

Births - Deaths = r
r= the rate of increase in a population

r>0

Population is growing, more births that deaths

r=0

Population is not changing in size births = deaths

r

Population is shrinking More deaths than births

logistical Growth

a populations growth rate increases rapidly in the early stage and slows down as N approaches K (carrying capacity) and r will eventually become 0

Exponential growth

A growth in which the rate is proportional to the increasing number or size in an exponential

Density independent factors

not influenced by a species population size. All species populations in the same ecosystem will be similarly affected, regardless of population size. Factors include: weather, climate and natural disasters. (abiotic)

Density Dependent Factors

any force that affects the size of a population of living things in response to the density of the population usually biotic (competition for food and water)

Biodiversity

The total variation of life along all levels of the biological hierarchy

Genetic drift

A change in allele frequency in a population due to chance

Gene pool

Sum of all the alleles in a population

Allele frequency Equation

Gene Flow

The transfer of genetic material from one population to another. (usually leads to equalizing of populations)

Allele frequency

Represents the possibility of a gene variant in a population

Genotype frequency

Represents the possibility of a genotype variant in a population

Hardy Weinberg Equilibrium

p^2+2pq+q^2=1

Assumptions of hardy Weinberg equilibrium

1. No random mating
2. No Natural selection
3. No genetic drift
4. No gene flow
5. No mutations

Adaption

A feature that has become common in a population through natural selection because it provides some improved function increasing fitness

Natural Selection

The process through which populations of living organisms adapt and change.

Directional selection

Occurs when individuals with traits on one side of the mean in their population survive better or reproduce more than those on the other.

Stabilizing Selection

A type of natural selection in which genetic diversity decreases as the population stabilizes on a particular trait value.

Disruptive Selection

Occurs when individuals of intermediate phenotype are less fit than those of both higher and lower phenotype, such that extremes are favored.

INTERsexual Selection

members of one sex (usually females) choose members of the opposite sex. (leads to showy males to get females attention)

INTRAsexual Selection

Where members of the same sex compete with one other for members of the opposite sex.

Female choice

Females who choose which males to mate with, how long to mate, and even whose sperm will fertilize her eggs

Male Competition

Males compete for access to females, the amount of time spent mating with females, and even whose sperm gets to fertilize her eggs.

Founder effect

The reduction in genomic variability that occurs when a small group of individuals becomes separated from a larger population.

Bottleneck Effect

An extreme example of genetic drift that happens when the size of a population is severely reduced. Events like natural disasters, killing most individuals and leaving behind a small, random assortment of survivors.