BIO 101 unit 3

Discuss factors that may affect the Earth's carrying capacity for humans.

-access to food, renewable resources

List ways in which you can help prevent the loss of biodiversity.

-ecotourism -eating less meat/dairy products -fund developing countries to put money towards advanced technology rather than habitat destruction -recycle and reuse

Discuss the potential future of the human population and what factors would help reduce growth rates.

-improve female literacy -education access

Explain population growth rate and how it has affected the human population.

-improved medical care, sanitation, and nutrition growth rate=birth rate-death rate

List and describe the consequences of extinction.

-loss or resources: some organisms are useful for medicines -habitat fragmentation threatens large predators -disrupted energy and chemical flows

Explain why populations go through a demographic transition.

-period when birth rates are dropping toward lowered death rates -countries that pass through swiftly are smaller (United States) -countries that pass through slowly are larger (India)

Compare evolution to alternative hypotheses for life's origin and diversity

1. A supernatural creator is not observable/measurable, there's no way to determine the existence of such an entity through the scientific method

Understand the misconceptions about natural selection

1. Natural selection doesn't result in perfect organisms 2. Natural selection doesn't have a "goal" 3. Individuals can't evolve

List the four observations that lead to the inference of natural selection, and describe how natural selection drives evolution.

1. Organisms in the population vary 2. Variation among organisms can be passed onto offspring 3. More organisms are produced than survived 4. An organism's survival is not random

Summarize and explain the evidence supporting the theory of evolution.

1. Scientists contend that apes and humans are so similar because both are from a common biological ancestor 2. Darwin noted that Linnaeus's hierarchal classification system implied evolutionary relationships among organisms 3. Reject only static model hypothesis

Combination drug therapy:

: aka "drug cocktail therapy". The greater of the number of drugs used, the greater the number of changes that are required in the bacterial genome for resistance to develop

Population bottleneck:

: is a sharp reduction in the size of a population due to environmental events (such as earthquakes, floods, fires, disease, or droughts) or human activities (such as genocide).

Founder effect

: type of sampling error that occurs when a small subset of individuals emigrates from the main population and begins a new population, leading to differences in the gene pools of both

Population

A group of organisms of one species that interbreed and live in the same place at the same time

Keystone species:

A species that has an unusually strong effect on the structure of the community it inhabits.

Tuberculosis:

Degenerative lung disease caused by infection with the bacterium Mycobacterium tuberculosis

Define carrying capacity and list density-dependent and independent factors that affect population growth.

Density dependent: food, water, shelter, spread of disease, accumulation of waste Density independent: weather fluctuations, natural disasters

Explain the evidence that suggests we are entering a mass extinction and list the causes of this extinction.

Evidence: extinction rates are 50-100 times greater, 29% amphibians are in danger of extinction Causes: loss/degradation of habitat, introduction of nonnative species, overexploitation, effects of pollution

Explain the relationship between natural selection and genetics (the modern synthesis)

Genetic variation is essential for natural selection because natural selection can only increase or decrease frequency of alleles that already exist in the population.

Define a biological race and explain why human "races" are not biological groups.

Human races have never been truly isolated from each other, and therefore haven't evolved into separate biological races

Homologous structures:

If two or more species share a unique physical feature, such as a complex bone structure or a body plan, they may all have inherited this feature from a common ancestor

Explain the three types of species interactions.

Mutualism: two species benefit from one another Commensalism: one species benefits from the other, other is unaffected Parasitism: organism that cause harm to a host

List the factors that have influenced the human population growth rate.

Populations may grow exponentially for a while, but eventually they reach the environment's carrying capacity.

Competitive exclusion:

Reduction or elimination of one species in an environment resulting from the presence of another species that requires the same or similar resources

Homology:

Similarity in characteristics because of common ancestry

Isolations:

Spatial isolation: a liger is a cross with a tiger (from Asia) and a lion (form Africa) Behavioral isolation: courtship dance in blue footed boobies Mechanical isolation: lock and key genital in some insects Temporal isolation: differences in timing of flowering

Biogeography:

Study of the geographic distribution

Radiometric dating:

Technique that relies on radioactive decay to estimate a fossil's age

Population growth rate:

The rate, or speed, at which the number of organisms in a population increases. this can be calculated by dividing the change in the number of organisms from one point in time to another by the amount of time in the interval between the points of time

Define the theory of evolution and explain what a scientific theory is.

Theory of Evolution: all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual's ability to compete, survive, and reproduce. Scientific Theory: well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.

Summarize the relationship between natural selection and drug resistance in disease-causing microbes.

When someone takes an antibiotic, they feel much better. The weak bacterias die out, but the strong ones stay. When the medicine stops, the strong ones grow, creating their offspring to also be resistant.

Genetic drift

a change in allele frequency that occurs due to change

Ecosystem:

all of the organisms in a given area, with their nonbiological environment

Population:

all the of individuals of a species within a given area. Exhibit structure which includes the spacing of people and their density

Speciation (both allopatric and sympatric):

allopatric: populations that are isolated from each other by distance or a barrier, may change overtime sympatric: Separation between the gene pools of two population may occur even if the populations are living near each other, requires reproductive isolation

Variation:

an individual in a population that differs genetically from other individuals in the population

Suboptimal structures

are structures that a given sequence could fold into aside from the minimum free energy structure. As an RNA folds, it may pass through several suboptimal structures before it adopts a stable structure.

Analogous structures:

arious structures in different species having the same function but have evolved separately, thus do not share common ancestor

Antibiotic-resistant

characteristics of certain bacteria; a physiological characteristic that permits them to survive in the presence of antibiotics

Antibiotics:

chemicals that kills/disables bacteria

Anatomical homology:

comparison of body structures in different species. Anatomical similarities indicate common ancestry. Ex. Bats wing, whale flipper, human arm, etc.

Extinction:

complete loss of species or subspecies, while threatened organisms are at high risk of becoming endangered

Community:

consisting of all the organisms living together in a habitat area

Biodiversity:

entire variety of living organisms

Allele frequency:

evolution results in a change in allele frequency in a population. It is the percentage of the gene copies in a population that are of a certain form, or allele

Food chain and food web:

food chain: energy flows in one direction within ecological system food web: . Linage among organisms inhabiting different niches in a community (food web)

Fossils and fossil record:

fossils are preserved remnants or impressions left by organisms that lived in the past. The ordered array in which fossils appear within layers of sedimentary rock indicates their relative age. Oldest fossils are bacteria from 3.5 billion years ago.

Species

group of closely related organisms that are very similar to each other and are usually capable of interbreeding and producing fertile offspring.

Biological evolution

is a change in the characteristics of a biological population that occurs over the course of generations.

Net primary productivity:

is a measure of the amount of food energy available on the planet.

Hybrid sterility:

mules, the cross with horse and donkey are sterile

Introduced species:

organisms brought by human activity, are often dangerous to natives because are not coevolved with them.

Common descent:

part of the theory of evolution that states that all life shares a common ancestor

Demographic transition:

period between when death rates in a population fall due to improve technology and birth rates fall due to voluntary limitation of pregnancy

Habitat:

place where organism obtain, food, water, shelter, and space

Natural selection:

process by which individuals with certain traits have greater survival and reproduction than those who lack these traits, resulting in an increase in the frequency of successful alleles and a decrease bad ones

Biological race:

races are populations of a single species that have diverged from each other because of isolation of their gene pools

Fitness:

relative survival and reproduction of one variant compared to others in the same population

Hybrid inviability:

sheep and goats are too different genetically to produce healthy young

Vestigial traits:

similarities between functional traits in one organism and seemingly nonfunctional or greatly reduced features in another

Punctuated equilibrium:

speciation events are sudden, results in dramatic changes within a few thousand years and are followed by many thousands/millions of years of little things

Gradualism

speciation occurred over millions of years as tiny changes gradually accumulated

Gamete incompatibility

sponge sperm won't fertilize wrong species eggs

Population pyramid:

summary of the number and proportions of individuals of each sex and each age group

Assortative mating:

tendency for people to mate with other people who are like themselves

Natural selection

the differential survival and reproduction of individuals in a population, brought about the evolutionary change. is the process by which populations adapt to their changing environment?

Adaptations:

traits that increase an individual's relative fitness to its environment

Competition:

two species of organisms that both require the same resources in a habitat

Sexual selection:

when traits influence the likelihood of mating, the trait is under the natural selection form called sexual selection

Demographic momentum:

young populations will continue to swell