Biology Test 2

• Phenotype gene comes from sex chromosome
• Trait typically appears in every generation

• Phenotype gene does not come from sex chromosome
• If both parents are heterozygous, child will have a 25% chance of being affected

• Alleles segregate into different haploid cells that eventually give rise to gametes
• During fertilization, male and female gametes randomly combine with each other

• Males show disorder more than females
• Son cannot inherit disorder from his father

Genes on different chromosomes segregate independent of one another

• Prophase: chromosomes composed of two chromatids
• Metaphase: chromosomes align at spindle equator
• Anaphase: sister chromatids of chromosomes separate
• Telophase: two nuclei (2n)

• Probability that two or more independent events will occur is equal to the product of their individual probabilities
• 1/2 x 1/2 = 1/4

• It depends on how many loci are heterozygous and on different chromosomes
• 2 alleles can be made for each heterozygous locus
• AAFfEdYyDDIIKKJj = 16

• Probability that one of two or more mutually exclusive outcomes will occur is the sum of the probabilities
• 1/4 + 1/4 = 1/2

Occurs when natural selection maintains stable frequencies of two or more phenotypic forms in a population

• No mutation
• Random mating
• Gene doesn't affect survival or reproduction
• Large population
• No immigration/emigration

Allele frequency = (number of copies of a specific allele in population)/(Total number of all alleles for that gene in a population)

Genotype frequency = (number of individuals with a particular genotype in population)/(Total number of individuals in a population)

Actual number of surviving offspring with a particular genotype produced between generations

Number of surviving offspring of one genotype compared to a different genotype

Individuals of one extreme phenotype favored

• Individuals with intermediate phenotype favored
• Extreme phenotype selected against

• Both extreme phenotypes favored
• Intermediate phenotypes selected against

• Genetic drift is significant in small populations
• Causes allele frequencies to change at random
• Can lead to a loss of genetic variation within populations
• Can cause harmful alleles to become fixed

Genetic variation that appears to confer no selective advantage or disadvantage

Multiple alleles at multiple loci interacting and affecting a trait

Alleles at a single locus may affect 2 or more traits

A continuous range of small differences in a given trait among individuals

Some genes are not found on the chromosomes in the cell nucleus. Like in mitochondria and chloroplasts

Mother

Father

Asexual reproduction passes on 100% of genetic info but sexual reproduction only passes on 50% from the mother

When members of one sex compete for territory and resources in order to get a mate

• Female choice
• Females choose male mates based on a criterion that reflects ability to provide resources and/or quality of genes

Change of appearance, such as molting into new feathers, during breeding season to attract new mates

Influence a particular factor has on the ability of an organism to survive and reproduce

• Lineage splits, isolated populations diverge
• Branching pattern

• Changes occur within a single lineage (no branching)
• Gene flow throughout process

Taxon contains a common ancestor and all of its descendants

Taxon contains its most recent common ancestor, but does not contain all the descendants of that ancestor

Common ancestor(s) not in group

Derived or specialized character or character state

An ancestral or primitive character or character state

• Long-term result of microevolutionary processes
• Patterns and trends among major lineages

When a species branches off from its native habitat and variation occurs

• Natural selection
• Genetic drift
• Mutation
• Gene flow

• Something preventing fertilization between 2 groups of the same species
• Habitat isolation
• Temporal "    "
• Behavioral "   "
• Mechanical "   "
• Gametic  "  "

Species are kinds of organisms that are reproductively isolated from one another

Species occupy different ecological niches

Members of the same species recognize one another as potential mates

Species is a basal cluster of organisms that is distinct from other such clusters and shows a pattern of ancestry and descent

• Each new species evolves continuously over long spans of time
• Large phenotypic differences that produce new species are due to the accumulation of many small genetic changes

• Tempo of evolution more sporadic
• Species in equilibrium for long periods and then short rapid bursts of changes

No contact between populations

Populations share a border area

Continuous contact between populations

2 different habitats

Species specific behaviors

Physically cannot mate

Gametes are shared purely randomely

• Two species can breed but something prevents their offspring from thriving
• Allopatric Speciation
• Sympatric Speciation

A species is a set of individuals with morphological features in common.

• Anther and filament
• Male gametes in plants

• Pistil, stigma, ovary/carpels
• Female gametes in plants

Animals move pollen from one flower to another

• Primary: food, shelter, other needed materials
• Secondary: odor, visual cues

Plants that mimic females of pollinator species to trick it into mating the flower and collect pollen

• Anchors the plant
• Used to absorb water and ions

• Consists of supporting stems, photosynthetic leaves, and reproductive flowers
• Repetitive units consist of internode, node, leaf, and axillary bud

Point of attachment of leaf to stem

Area of stem between two nodes

Flattened part of leaf

Stalk of leaf

Angle between petiole/blade and stem

Develops into branches with leaves or may form flowers

Extends the shoot system during the growing season

• Dermal: outer protective cover
• Ground: function in storage, photosynthesis, and secretion
• Vascular: conducts fluids and dissolved substances

• Parenchyma: function in storage, photosynthesis, and secretion
• Collenchyma: provide support and protection, kinda soft
• Sclerenchyma: dead, hard cells that provide protection and support

• Fibers: long, slender cells that are usually grouped in strands
• Sclereids: variable shape, often branched, may occur singly or in groups

• Xylem: principle water-conducting tissue.
• Phloem: nutrient transportation