bio midterm

What does the term 'biotic' refer to in an environment?

Biotic refers to the living parts of the environment.

What does the term 'abiotic' mean?

Abiotic refers to the non-living elements such as air, water, and climate.

List the levels of organization in ecology.

Species, Population, Community, Ecosystem, Habitat, Niche.

What is a predator-prey relationship?

A relationship where predators (carnivores and omnivores) depend on prey for food.

Define symbiosis.

A close relationship between two different species.

What is commensalism?

A symbiotic relationship where one species benefits and the other is neither helped nor harmed.

What is mutualism?

A symbiotic relationship where both species benefit.

Describe parasitism.

A relationship where one organism (the parasite) benefits at the expense of another which is harmed.

What are autotrophs?

Organisms that produce their own food.

What is the role of herbivores in an ecosystem?

Herbivores are organisms that consume plants.

What do scavengers do in an ecosystem?

Scavengers clean up dead organic matter.

Define decomposers.

Organisms that break down dead material and recycle nutrients.

What does a food chain illustrate?

The flow of energy through an ecosystem.

What is the significance of energy pyramids?

They show the relative amount of energy available at each trophic level.

What is carrying capacity?

The maximum number of individuals of one species that an environment can support.

What factors threaten biodiversity?

Habitat loss, global warming, pollution, and overpopulation.

Define covalent bonds.

Bonds formed when atoms share electrons.

What are ionic bonds?

Bonds formed by the transfer of electrons between atoms.

What is diffusion?

The movement of particles from an area of high concentration to an area of low concentration.

What are carbohydrates?

Organic compounds made up of simple sugars.

Differentiate between prokaryotes and eukaryotes.

Prokaryotes lack a membrane-bound nucleus, while eukaryotes have complex cells with membrane-bound organelles.

What is the function of ribosomes?

They synthesize proteins.

What occurs during mitosis?

The process where a single cell divides to produce two daughter cells that are identical to the original.

What is the phenotype?

The physical appearance of an organism.

Define homozygous alleles.

When an organism has two of the same alleles for a trait.

What is meant by the law of independent assortment?

Genes for different traits are inherited independently of one another.

What happens during crossing over?

The exchange of genetic material between non-sister chromatids during meiosis.

What can pedigree charts indicate?

Genetic relationships and the inheritance of traits.

What does it mean for a variable to be independent?

It's the variable that is changed or controlled in a scientific experiment.

What is a dependent variable?

It's the variable that is measured or tested in an experiment.