AP Biology Key Ideas and Concepts

These flashcards cover the essential vocabulary and concepts from AP Biology as presented in the lecture notes.

Evolution

The theory that organisms descended from common ancestors, demonstrating diversity in form, function, and lifestyle.

Natural Selection

A process where traits in organisms that are favorable for survival and reproduction become more common in a population.

Taxonomy

The discipline of identifying, naming, and classifying organisms according to shared characteristics.

Metabolism

The biochemical processes that occur within a living organism to maintain life, including the conversion of energy.

Photosynthesis

The process by which green plants and some organisms convert sunlight into chemical energy, typically producing glucose and oxygen.

Homeostasis

The ability of living organisms to maintain stable internal conditions despite changes in the external environment.

Genetic Mutation

Changes in the DNA sequence that can lead to variations in traits, which may provide a selective advantage.

Emergent Properties

Traits and characteristics that arise from the interaction of different components within a biological system.

Hydrogen Bonding

Weak attractive forces that occur when a hydrogen atom bonded to a highly electronegative atom interacts with another electronegative atom.

Cohesion

The ability of water molecules to stick together due to hydrogen bonding, contributing to surface tension.

Phospholipids

Molecules that consist of hydrophilic heads and hydrophobic tails, forming the structural basis of cell membranes.

ATP (Adenosine Triphosphate)

The primary energy carrier in cells, providing energy for cellular processes.

Cell Theory

The theory stating that all living things are composed of cells, which are the basic units of life.

Prokaryotic Cells

Simple, unicellular organisms that lack membrane-bound organelles, including a nucleus.

Eukaryotic Cells

More complex cells that contain a nucleus and membrane-bound organelles.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in four haploid cells.

Sympatric Speciation

The evolution of new species from a common ancestral species while inhabiting the same geographic region.

Biodiversity

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

Haploid

A cell that contains a single set of chromosomes, typically seen in gametes (sperm and egg).

Selective Pressure

Environmental factors that influence which individuals survive and reproduce within a population.

Allele Frequency

The relative frequency of an allele at a genetic locus in a population.

Fossil Evidence

Remains or traces of organisms that provide insights into the evolutionary history and changes over time.

Gene Flow

The transfer of genetic material between populations through migration or interbreeding.

Evolution

The process through which different kinds of living organisms develop and diversify from earlier forms during the history of the Earth. This theory proposes that species change over time through inherited traits, with variations influenced by environmental factors leading to natural selection.

Natural Selection

A fundamental concept of evolution proposed by Charles Darwin, describing the mechanism by which individuals with advantageous traits survive and reproduce more effectively than others. Over generations, these favorable traits become more common in the population, driving the evolution of species.

Taxonomy

The branch of biology that deals with naming, describing, and classifying organisms. It involves hierarchical ranks such as domain, kingdom, phylum, class, order, family, genus, and species, which reflect the evolutionary relationships among various life forms.

Metabolism

The total of all the biochemical processes that occur within a living organism, including anabolism (building up simple substances into complex ones) and catabolism (breaking down complex substances into simpler ones). Metabolism enables organisms to grow, reproduce, maintain their structures, and respond to environmental changes.

Photosynthesis

The biochemical process used by green plants, algae, and some bacteria to convert light energy, usually from the sun, into chemical energy stored in glucose. This process requires carbon dioxide and water and releases oxygen as a byproduct, making it essential for life on Earth.

Homeostasis

The ability of living organisms to maintain stable internal conditions such as temperature, pH, and ion concentration despite external environmental fluctuations. Homeostasis is critical for the proper functioning of cells and overall organismal health.

Genetic Mutation

A change in the nucleotide sequence of an organism's DNA, which can result in altered traits. Mutations can occur naturally or be induced by environmental factors. They can be beneficial, neutral, or harmful, and are a source of genetic variation that fuels evolution.

Emergent Properties

Complex traits or functions that arise from the interactions and relationships between simpler components within a system. In biological contexts, emergent properties can be seen in how simple cellular components interact to produce complex behaviors or characteristics in living organisms.

Hydrogen Bonding

A weak, non-covalent attraction between a hydrogen atom covalently bonded to a highly electronegative atom (like oxygen or nitrogen) and another electronegative atom. This type of bonding is responsible for many of water's unique properties, including its high surface tension and solvent capabilities.

Cohesion

The property of water molecules to stick together due to hydrogen bonding, which results in phenomena such as surface tension. Cohesion is essential for processes like water transport in plants and the formation of water droplets.

Phospholipids

Amphipathic molecules that consist of a hydrophilic (water-attracting) phosphate 'head' and two hydrophobic (water-repelling) fatty acid 'tails'. These molecules are crucial for forming cell membranes, providing a barrier that separates the cell interior from the external environment.

ATP (Adenosine Triphosphate)

A high-energy molecule that serves as the primary energy currency of cells. ATP is generated during cellular respiration and is used in various biochemical reactions to power cellular processes such as muscle contraction, nerve impulse propagation, and biochemical synthesis.

Cell Theory

A fundamental principle in biology proposing that all living organisms are made up of cells, which are the basic units of life. The theory also states that all cells arise from pre-existing cells, emphasizing the continuity of life and cellular processes.

Prokaryotic Cells

Simple, unicellular organisms characterized by the lack of a defined nucleus and membrane-bound organelles. Prokaryotes, which include bacteria and archaea, have a more straightforward cell structure but can be incredibly diverse biologically.

Eukaryotic Cells

More complex cells that contain a nucleus and various membrane-bound organelles, allowing for compartmentalized cellular functions. These cells make up multicellular organisms such as plants, animals, and fungi, and exhibit greater structural and functional diversity.

Meiosis

A specialized form of cell division that occurs only in the production of gametes (sperm and eggs). Meiosis reduces the chromosome number by half through two successive divisions, creating four non-identical haploid cells, which are crucial for sexual reproduction.

Sympatric Speciation

The evolutionary process where new species arise from a common ancestor while sharing the same geographic area. This type of speciation can occur due to reproductive barriers, behavioral differences, or ecological niche differentiation without geographic separation.

Biodiversity

The variety of life on Earth, encompassing different species, genetic diversity within species, and the variety of ecosystems. Biodiversity is essential for ecosystem resilience and is crucial for providing resources and ecosystem services that sustain human life.

Haploid

A cell that contains only one complete set of chromosomes, typically observed in gametes (sperm and egg cells). In sexually reproducing organisms, haploid cells combine during fertilization to form a diploid organism with two sets of chromosomes.

Selective Pressure

Any environmental factor that influences the survival and reproductive success of individuals within a population. Selective pressures can lead to evolution by favoring individuals with advantageous traits that enhance survival and reproduction.

Allele Frequency

The relative proportion of a specific allele (variant of a gene) at a given genetic locus in a population. Changes in allele frequency over time can indicate evolution within the population and are influenced by factors such as mutation, selection, gene flow, and genetic drift.

Fossil Evidence

Physical remains or traces of organisms preserved in geological layers, providing insight into the history of life on Earth. Fossils can reveal information about evolutionary changes, species interactions, and past environments.

Gene Flow

The transfer of genetic