Spring Semester Exam Review and Key Concepts in Biology

Natural Selection

The process of species adapting to their environment to increase chances of survival and reproduction.

Genetic Variation

Differences in DNA among individuals that contribute to diversity within a species.

Competition

The struggle between organisms for limited resources such as food, space, and mates.

Survival of the Fittest

The concept that individuals best adapted to their environment are more likely to survive and reproduce.

Descent with Modification

The process by which species evolve over time through adaptations.

Fossil Records

Remains or traces of organisms from the past, providing evidence for evolution.

Anatomical Structures

Physical features of organisms that can provide evidence for evolutionary relationships.

Homologous Structures

Anatomical features that are similar in different species due to shared ancestry.

Analogous Structures

Anatomical features that serve similar functions in different species but do not share a common ancestor.

Vestigial Structures

Body parts that have lost their original function through evolution.

Embryology

The study of embryos, which can show similarities in development among different species.

Biogeography

The study of the geographical distribution of species, implying common ancestry.

Biochemical Evidence

The comparison of DNA sequences among species to determine relatedness.

Observable Events

Rapid evolution that can be witnessed, such as changes in pathogens or pests.

Gradualism

The theory that evolution occurs slowly and steadily over time.

Stasis

A period in which a species remains unchanged for a long time.

Punctuated Equilibrium

The theory that evolution occurs in rapid bursts followed by long periods of stability.

Directional Selection

A type of natural selection that favors one extreme phenotype over others.

Stabilizing Selection

A type of natural selection that favors average phenotypes and reduces variation.

Disruptive Selection

A type of natural selection that favors extreme phenotypes at both ends of the spectrum.

Gene Flow

The transfer of genetic material between populations, increasing genetic diversity.

Genetic Drift

Random changes in allele frequencies in a population, often due to chance events.

Hardy-Weinberg Principle

A principle that describes the genetic equilibrium in a population under certain conditions.

SPECIATION

When one species diverges into two species.

GEOGRAPHIC ISOLATION

Physical isolation between two populations.

REPRODUCTIVE ISOLATION

Can no longer interbreed.

CLADOGRAMS

A diagram that shows the evolutionary relationships among various biological species.

DERIVED CHARACTERISTICS

Gained traits.

GENETIC DIVERSITY

Is important because it allows for better survival (adapting to changing environments).

HOMEOSTASIS

Maintaining internal balance; essential for survival.

SKELETAL SYSTEM

Provides support and structure.

ENDOCRINE SYSTEM

Produces hormones.

CIRCULATORY SYSTEM

Transports substances.

MUSCULAR SYSTEM

Facilitates movement.

REPRODUCTIVE SYSTEM

Produces gametes.

IMMUNE SYSTEM

Defends against illness.

EXCRETORY SYSTEM

Removes waste.

DIGESTIVE SYSTEM

Breaks down food for energy.

RESPIRATORY SYSTEM

Facilitates the exchange of O2 and CO2.

INTEGUMENTARY SYSTEM

Acts as a barrier.

NERVOUS SYSTEM

Sends and receives signals.

NEGATIVE FEEDBACK

Used to maintain balance.

POSITIVE FEEDBACK

Used to complete a job.

VIRUSES

Are not considered living, need a host cell to do anything.

GLYCOPROTEINS

Genetic material for infecting specific cells.

ENVELOPE

For protection (not all viruses have this).

CAPSID

Made of protein for protection.

LYTIC REPRODUCTION

Quicker reproduction.

LYSOGENIC REPRODUCTION

Slower reproduction.

LINES OF DEFENSE

1st line: Physical barrier; 2nd line: Inflammatory response; 3rd line: Targets specific antigens.

SECONDARY IMMUNE RESPONSE

Response is FASTER and STRONGER upon exposure to a pathogen.

PRIMARY IMMUNE RESPONSE

Response is WEAK and SLOW upon initial exposure to a pathogen.

PLANT CELLS

Cells that have chloroplasts, a large central vacuole, and a cell wall.

PLANT TISSUES

Types of tissues in plants including vascular, ground, and dermal.

VASCULAR TISSUE

Transports materials in plants.

GROUND TISSUE

Stores materials in plants.

DERMAL TISSUE

Outer covering of plants.

XYLEM

Vascular tissue that transports water and minerals.

PHLOEM

Vascular tissue that transports sugars.

ROOTS

Organs that absorb water and anchor the plant.

STEMS

Organs that support the plant and transport materials.

LEAVES

Site of photosynthesis in plants.

TRANSPIRATION

Process of movement and evaporation of water in plants through a guard cell.

BRYOPHYTES

Non-vascular plants that reproduce with spores.

PTERIDOPHYTES

Vascular plants that reproduce with spores.

GYMNOSPERMS

Vascular plants with naked seeds and no flowers.

ANGIOSPERMS

Vascular plants with covered seeds, flowers, and fruits.

STIGMA

Part of the flower that collects pollen.

PETAL

Part of the flower that attracts pollinators.

ANTHER

Produces pollen in the flower.

STYLE

Pollen tubes travel through this part of the flower.

OVARY

Protects plant zygotes and helps develop pollen.

SEPAL

Protects budding flowers.

SEED DISPERSAL

Increases chance of survival by reducing competition.

AUXINS

Hormones that promote lengthening in plants.

CYTOKININS

Hormones that help with cell division.

GIBBERELLINS

Hormones that cause dramatic increases in size.

ETHYLENE

Hormone involved in the ripening of fruit.

PHOTOTROPISM

Response of plants to a light source.

GRAVITROPISM

Response of plants to gravity.

THIGMOTROPISM

Response of plants to touch.

PHOTOSYNTHESIS

Process where plants convert light energy into chemical energy, represented by the equation 6CO2 + 6H2O → C6H12O6 + 6O2.

CELLULAR RESPIRATION

Process where cells convert glucose and oxygen into carbon dioxide and water, represented by the equation C6H12O6 + 6O2 → 6CO2 + 6H2O.

BIOSPHERE

The global sum of all ecosystems.

BIOME

Large ecological areas on the earth's surface with distinct plant and animal groups.

ECOSYSTEM

A community of living organisms and their physical environment interacting as a system.

COMMUNITY

A group of different species living together in one area.

POPULATION

A group of individuals of the same species living in a specific area.

INDIVIDUAL

A single organism.

AUTOTROPH

Organisms that make their own food.

HETEROTROPH

Organisms that consume others for food.

FOOD CHAIN

A linear sequence that shows the flow of energy from one organism to another.

FOOD WEB

A complex network that shows the flow of energy from multiple organisms.

DECOMPOSER

Organisms that break down dead organic matter.

QUATERNARY CONSUMER

An organism that is at the top of the food chain, feeding on tertiary consumers.

TERTIARY CONSUMER

An organism that feeds on secondary consumers.

SECONDARY CONSUMER

An organism that feeds on primary consumers.

PRIMARY CONSUMER

An organism that feeds on producers.

PRODUCER

Organisms that produce energy through photosynthesis.

PREDATOR-PREY

A relationship where one organism captures and feeds on another.