Honors Biology 2025 Spring Final Review Guide

Flashcards for Honors Biology 2025 Spring Final Review

Mechanical vs. chemical breakdown (Digestive system)

Mechanical is the physical breakdown of food, while chemical is the breakdown of food using enzymes.

Organs and Functions of Digestive System

Organs include mouth, esophagus, stomach, small intestine, large intestine, liver, pancreas. Functions include breaking down food, absorbing nutrients, and eliminating waste.

Alveoli

Site of gas exchange between air and blood.

Diffusion

Gas exchange from high concentration to low concentration.

Major Vessels (Circulatory system)

Arteries carry blood away from the heart; veins carry blood to the heart.

Renal Arteries and Veins

Renal arteries supply blood to the kidneys; renal veins drain blood from the kidneys.

Integumentary System function

Covers and protects the body.

Biosphere

The part of the Earth inhabited by living organisms.

Biodiversity

The variety of life in the world or in a particular habitat or ecosystem.

Abiotic & Biotic Factors

Nonliving factors (e.g., temperature, sunlight) and living factors (e.g., plants, animals) in an environment.

Habitat vs. Niche

The place where an organism lives vs. the functional role of an organism in its environment.

Autotroph vs. Heterotroph

Producers that make their own food vs. Consumers that obtain energy by feeding on other organisms.

Food Chain vs. Food Web

A sequence of organisms through which energy and nutrients move vs. a network of interconnected food chains.

Energy Pyramid

A graphical representation of the energy flow in a community.

Keystone Species

A species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.

Species Interaction Types

Symbiosis: interaction between different organisms living in close physical association. Mutualisam: both organisms benefit. Commensalism: one organism benefits and the other is not affected. Parasitism: one organism benefits and the other is harmed. Predation: one organism kills and consumes the other.

Carrying Capacity

The maximum population size of a species that an environment can sustain indefinitely.

Cellular Respiration

Converts energy in food (glucose) to ATP.

Photosynthesis

Converts energy in sunlight into food (glucose).

ATP

A molecule that carries energy within cells.

Adaptation

A trait that enhances survival and reproduction in a specific environment.

Types of Selection

Natural: differential survival and reproduction of individuals due to differences in phenotype. Sexual: mate choice. Artificial: breeding by humans.

Microevolution vs. Macroevolution

Small-scale changes in allele frequencies in a population vs. large-scale evolutionary changes that result in the formation of new taxonomic groups.

Evidence of Evolution structures

Homologous: structures with shared ancestry. Analogous: structures with similar function but different ancestry. Vestigial: structures with no apparent function, representing evolutionary remnants.

Types of Selection

Disruptive: favors individuals at both extremes of a distribution. Stabilizing: favors intermediate variants. Directional: favors individuals at one end of a distribution.

Mutation

A change in the DNA sequence.

Speciation

The process by which new species arise.

Allopatric vs. Sympatric Speciation

Allopatric: speciation due to geographic isolation. Sympatric: speciation in the same geographic area.

Genetic Drift

Random changes in allele frequencies in a population.

Fitness

The ability of an organism to survive and reproduce in its environment.

Phylogenetic Tree

A diagram that depicts the evolutionary relationships among organisms.

Morphology

The study of the form and structure of organisms.

Inheritance of Traits

The passing of traits from parents to offspring.

Punnett Square

A diagram used to predict the genotypes and phenotypes of offspring.

Homozygous vs. Heterozygous

Having two identical alleles for a gene (e.g., AA or aa) vs. having two different alleles for a gene (e.g., Aa).

Dominant vs. Recessive

An allele that masks the expression of another allele vs. an allele whose expression is masked by another allele.

Phenotype vs. Genotype

The physical expression of a trait vs. the genetic makeup of an organism.

Genetic terms

Polygenic: trait controlled by mulitple genes. Epistasis: one gene affects the expression of another. Pleiotropy: one gene affects multiple traits. Incomplete dominance: heterozygous phenotype is intermediate between homozygous phenotypes. Sex-linked traits: traits determined by genes on the sex chromosomes.

Variables in Experimental Design

Independent: variable that is manipulated. Dependent: variable that is measured. Constant: variable that is kept the same.

Control vs. Experimental Groups

Group that does not receive the treatment vs. group that receives the treatment.

Monomer vs. Polymer

A monomer is a small building block, while a polymer is a large molecule made of many monomers.

Condensation vs. Hydrolysis Reaction

Condensation: removes water to join monomers. Hydrolysis: adds water to break polymers.

Homeostasis

Maintenance of stable internal conditions in an organism.

Positive vs. Negative Feedback

Positive: amplifies the change. Negative: reverses the change.

Eukaryotic vs. Prokaryotic Cells

Eukaryotic: has a nucleus and other membrane-bound organelles. Prokaryotic: no nucleus or other membrane-bound organelles.

Cell Transport Types

Osmosis: diffusion of water. Facilitated diffusion: diffusion with the help of membrane proteins. Diffusion: movement from high to low concentration. Active transport: movement against concentration gradient (requires energy). Endocytosis: taking substances into the cell. Exocytosis: releasing substances out of the cell.

Solution Types

Hypotonic: lower concentration of solute. Hypertonic: higher concentration of solute. Isotonic: equal concentration of solute.

Structure of DNA

Double stranded and contains thymine.

Mitosis vs. Meiosis

Mitiosis: cell division that results in two identical daughter cells. Meiosis: cell division that results in four genetically unique daughter cells with half the number of chromosomes.

Crossing-over

Crossing-over is the exchange of genetic material between homologous chromosomes during meiosis.

Species definition

A group of organisms that can interbreed and produce fertile offspring.

Taxonomy Order

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Scientific Name Format

Genus species (italicized)

Bacteria

Unicellular prokaryotes with cell walls containing peptidoglycan.

why viruses are not considered living

They are not cellular and require a host to reproduce.