BIO001 Midterm 1 Vocab

Hypothesis

A proposed explanation for something that researchers have observed.

Prediction

A statement of an outcome that should occur if a hypothesis is correct.

Null Hypothesis

A hypothesis that represents the "not" or "no-effect" contrast to the hypothesis being tested.

Treatment (or experimental) group:

A group that experiences experimental conditions that conform to the mechanism proposed in the hypothesis.

Control group

A comparison group that represents the normal or no-treatment condition to contrast with groups that experience experimental manipulation.

Controlled conditions

Aspects of an experimental design that are used in both control and experimental treatments to eliminate bias among treatments and reduce influence from confounding factors.

Outcome variable

The variable that is measured in an experimental or observational study. It represents a quantity that is relevant to the hypothesis being tested.

Science

A human endeavor based on asking questions about the natural and physical world and answering them with measurable, verifiable evidence.

Pseudoscience

A tradition that tries to explain or predict natural and physical phenomena but 1) does not rely on measurable, verifiable evidence, and 2) invokes mysterious or unnamed mechanisms rather than known physical mechanisms.

King Philip Came Over From Great Spain

Kingdom, phylum, class, order, family, genus, species

Species richness

The total number of species present

Species evenness

the relative abundance of each species (# of each species)

Biodiversity

any type of variation that exists in biological systems, often discussed as variation in the species that occupy the same habitat at the same time

Functional group

a collection of species that have a distinctive structural or functional role in an ecosystem

Taxonomic group

hierarchical levels scientists use to classify organisms, both living and extinct, based on their shared physical and/or genetic characteristics (Domain, Kingdom, phylum, class, order, family, genus, species)

Biodiversity hotspots

regions that contain more than 1,500 endemic plant species and have lost at least 70% of their original area to anthropogenic uses

Climate

the average atmospheric conditions (temperature and precipitation) that a region experiences and how much those conditions vary across seasons and years; average weather conditions or patterns over long periods of time (mean annual precipitation, mean annual temperature, mean storm frequency or tracks)

Weather

the atmospheric conditions at any given moment; conditions in the atmosphere over a short period of time (current conditions, individual events)

Greenhouse effect

the process by which the atmosphere absorbs energy and prevents it from being radiated back out to space

Type II survivorship

organisms that demonstrate a relatively constant rate of mortality throughout their lifespan.

Type III Survivorship

organisms that demonstrate high levels of mortality during the early stages of their lifespan, decreasing significantly during middle and old age.

Type I Survivorship

Organisms that demonstrate low levels of mortality during the early and middle stages of their lifespan, increasing significantly at old age. 

Principle of Allocation

Each individual organism has a finite quantity of resources that it can use for all necessary life processes

Trade offs

The relationships between the benefits of resource investment decisions in one context compared to the costs of those decisions in another context. Usually appear as a negative relationship (downward slope).

Example of trade offs

investing more time in social activities may increase the number of friends you have (benefit), but will also decrease the amount of time available to study and likely result in lower grades (cost).

K-selected traits

Characteristics often associated with organisms that produce few offspring with low levels of juvenile mortality.  Population size is controlled by the carrying capacity of their environment. (Ex: Large body size, long life expectancy, slow growth, delayed reproduction, produce few large offspring, high parental investment, low juvenile mortality (Type I survivorship), predictable, stable environments, population sizes steady, pop size controlled by K (carrying capacity))

r-selected traits

Characteristics often associated with organisms that produce numerous offspring with high levels of juvenile mortality.  Population size is controlled by their growth rate. (Ex: Small body size, short life expectancy, rapid growth, early reproduction, produce many small offspring, little or no parental care, extreme juvenile mortality (Type III survivorship), unpredictable or variable environments, boom/bust population growth, pop size controlled by r (growth rate))

Endothermic

a reliance on metabolic processes for an animal to maintain a relatively constant internal body temperature

Thermoregulation

the processes an organism uses to manage its body temperature

Fundamental niche

the abiotic conditions the species can physiologically tolerate

Realized niche

the conditions a species can tolerate when impacted by interactions with other species (influenced by biotic factors)

Adaptation

The process by which a population experiences a change in its genotype in response to an environmental stressor across multiple generations.This change occurs much more slowly, usually across many generations, and is a result of natural selection.

Ectothermic

a reliance on the surrounding environment for an animal to regulate its internal temperature

Acclimation

The process by which an individual organism experiences a change in its phenotype in response to an environmental stressor within its own lifespan. This change is reversible and occurs very rapidly, sometimes in as little as a few minutes.

Bergmann’s Rule

the principle that an animal’s body size is generally correlated with the average habitat temperature

Allen’s Rule

the principle that an animal’s limb length is generally correlated with its average habitat temperature

Autotroph

self-feeding; taking chemical energy from non-organic molecules to drive its own processes (Ex: photoautotrophs, chemoautotrophs)

Heterotrophs

Other-feeding (Herbivores, carnivores, detritivores, etc.)

Isotonic solution

when the concentration of solutes and water molecules are equal on both sides of a membrane

Semipermeable membrane

a specialized barrier that only allows certain molecules or ions to pass through based on their size, electrical charge or other characteristics

Hypertonic solution

when the concentration of solutes in the solution is greater than the interior of a cell, causing water to flow out of the cell, resulting in the cell shriveling due to the loss of water.

Hypotonic solution

when the concentration of solutes in the solution is less than the interior of a cell, causing water to flow into the cell, resulting in the cell swelling due to the increase in water.

Optimal foraging theory

quantifies the benefits (in terms of energy content) of various prey choices and the costs (in terms of energy inputs for capturing, consuming, and digesting food) to predict the most energetically beneficial foraging choice. 

Photosynthesis

the process by which plants use light energy and CO2 from the atmosphere to build glucose molecules.

Herbivores

organisms that consume plant material

Carnivores

organisms that consume animal material

Omnivores

organisms that consume both plant and animal material

Detritivores

organisms that consume decaying dead plant and animal materials

Osmoregulation

refers to the processes an organism uses to maintain a proper concentration of water and ions within its bodily fluids. 

Liebig’s Law of the Minimum

Plant growth is not determined by the total amount of all resources available, but by the amount of the resource that is most scarce compared to how much the plant needs.

Density independent factors

conditions that affect population growth that do not change in impact in relation to the size of the population (Usually abiotic factors)

Exponential population growth

a growth pattern where a population’s size increases at an accelerating rate over time due to the presence of unlimited resources allowing for high reproductive rates.  

Density dependent factors

conditions that affect population growth that increase in impact in direct relation to the size of the population (Usually biotic factors)

Carrying capacity

the maximum population size an environment can sustain.

Logistic population growth

a growth pattern where resources are limited, thereby limiting both the growth rate and maximum size of the population.  As the population approaches the carrying capacity of the environment, the growth rate slows.

Population

Collections of organisms of the same species living in the same place at the same time

Open population

numbers change due to immigration and emigration from outside the population in addition to births and deaths

Closed population

numbers change only due to births and deaths

r

rate of growth of the population 

R₀

total reproductive rate of the population; the average number of offspring per individual

G

generation time; the average age of the parents across all offspring produced

l_x

survivorship

N_{x off}

Number of offpsrings

N_x

Number of individuals

m_x

fecundity (reproductive rates)

Gene

Segments of DNA that contain the information that molecular machines use to make a product—an RNA or protein—that functions in the organism

R - response to the selection (R = h²S)

The predicted magnitude of difference in the mean value of the trait between the first generation and the second generation (with selection occurring on the first generation before reproduction).

S - strength of selection (R = h²S)

The magnitude of difference between the average trait of the entire population and the average trait just for the smaller number of individuals who end up reproducing (the breeders). (The selected breeder’s average trait minus the whole population’s average trait)

Phenotype

What an individual looks or acts like

Fitness

The ability to produce viable offspring

h²- heritability of the trait (R = h²S)

The proportion of phenotypic variation attributed to the additive genetic variation which can be passed from parents to offspring.

DNA

A molecule that stores hereditary information in code form

Alleles

Versions of a gene

Mutation

Any change in DNA

Genotype

A listing of the alleles present in an individual

Natural selection

The process that changes allele frequencies when certain heritable traits are associated with different levels of reproductive success.

Evolution

A change in allele frequencies

Directional selection

Natural selection that favors an extreme phenotype; shifts phenotypes toward one extreme

Stabilizing selection

Natural selection that favors the average phenotype in the population and acts against extreme phenotypes.

Theory

An explanation or set of hypotheses that attempt to explain a large and pervasive phenomenon, meaning they that tie together a large suite of observations about how the natural world works.

Fitness

The ability to produce viable offspring. 

Artificial selection

When humans actively and consciously select which individuals will be the parents of the next generation.

Micro-evolution

Small shifts in allele frequency from one generation to the next

Macro-evolution

accumulation of genetic changes such that new species are formed

Disruptive (Diversifying) Selection

Phenotype at either extremes are the most successful

Negative Frequency Dependence

Phenotype that is rarest is the most successful

Positive Frequency Dependence

the most common phenotype is the most successful

Windward

Moist, rising air, (has a lot of precipitation)

Leeward

Dry, descending air (not much precipitation)