AP BIO EXAM REVIEW

Hydrogen Bonds in Water

Water molecules attract each other using hydrogen bonds, which are also responsible for water's cohesive and adhesive properties.

Cohesion

The attraction between molecules of the same kind, leading to surface tension and the ability of water to support itself.

Adhesion

The attraction between molecules of different kinds, such as water being adhesive to glass in capillary action.

Macromolecules

Large molecules like proteins and DNA, made up of smaller units called monomers, which are linked together through dehydration synthesis.

Carbohydrates

Molecules made of carbon, hydrogen, and oxygen, including monosaccharides (simple sugars), disaccharides, and polysaccharides like starch and cellulose.

Proteins

Complex macromolecules with primary, secondary, tertiary, and quaternary structures, crucial for various functions in cells.

Enzymes

Proteins that act as catalysts, lowering the activation energy of biochemical reactions, and named with the suffix -ase based on their substrate or function.

Cell Wall

A structural boundary in plant cells that provides protection, maintains shape, and prevents cellular rupture, made of cellulose and permeable to certain substances.

Water Potential

The measure of water's tendency to move by osmosis, influenced by pressure potential and solute potential, crucial for understanding water movement in cells.

ATP

Adenosine triphosphate, a molecule storing and releasing energy for cellular work, with a structure of ribose sugar, adenine base, and three phosphate groups.

Calvin Cycle

Process that converts chemical energy in NADPH and ATP into carbohydrates.

Chlorophyll

Pigment that absorbs light energy in photosynthesis.

Absorption spectrum

Shows the amount of light absorbed at different wavelengths.

Chloroplast

Organelle found in plant cells where photosynthesis occurs.

Thylakoids

Membrane-bound sacs in chloroplasts containing chlorophyll for light reactions.

Stroma

The cytoplasm of the chloroplast where the Calvin Cycle takes place.

Photosystems

Proteins embedded with chlorophyll that convert light energy into a flow of electrons.

Electron transport chain

Series of proteins that transfer electrons in photosynthesis and cellular respiration.

Glycolysis

Initial step of cellular respiration occurring in the cytoplasm.

Krebs cycle

Also known as the citric acid cycle, occurs in the mitochondrial matrix in cellular respiration.

Anaerobic respiration

Respiration without oxygen, producing less ATP than aerobic respiration.

Signal transduction pathway

Process of converting extracellular signals into cellular responses.

G-protein coupled receptors

Receptors that activate G proteins upon ligand binding.

Cell cycle

Series of events for cell growth and reproduction, including interphase, mitosis, and cytokinesis.

Meiosis

Cell division process that forms haploid gametes for sexual reproduction.

Meiosis

Cell division process where two haploid cells fuse to form a diploid cell, which then produces four haploid daughter cells.

Crossing Over

Exchange of genetic material between non-sister chromatids of homologous chromosomes during Prophase I of Meiosis, leading to genetic diversity.

Law of Segregation

States that alleles separate during gamete formation, with each gamete receiving one allele for each gene.

Law of Independent Assortment

Genes for different traits segregate independently during gamete formation, allowing for various combinations of alleles.

Genetic Code

Shared by all living systems, involves nucleic acids storing genetic information and ribosomes synthesizing proteins based on this information.

Monohybrid Cross

Examination of inheritance of one trait, involving two possible phenotypes and three possible genotypes.

Dihybrid Cross

Study of inheritance of two traits, often analyzed using Punnett squares to predict outcomes.

Chi Squared Hypothesis Testing

Statistical method to determine if differences in data are due to the independent variable or by chance.

Linked Genes

Genes located close together on the same chromosome, often inherited together, influencing genetic recombination.

Environmental Effects on Phenotype

Influence of environmental factors on gene expression, leading to phenotypic plasticity and varied phenotypes.

Replication

Process ensuring continuity of genetic information by copying DNA before cell division, involving enzymes like helicase and DNA polymerase.

Transcription

Enzyme-directed formation of mRNA from DNA, where RNA polymerase synthesizes mRNA in the 5' to 3' direction.

Translation

Process where mRNA is decoded by ribosomes to produce a specific polypeptide sequence, involving tRNA and rRNA.

Retrovirus Translation

Special case where viral RNA is converted into DNA by reverse transcriptase before being integrated into the host genome and translated.

Genetic Disorders

Result from mutations in alleles, with nondisjunction leading to abnormal chromosome numbers, such as in Triple X syndrome.

Codon Redundancy

Some amino acids are specified by more than one codon in the genetic code.

Start Codon

AUG is the start codon in mRNA, indicating the beginning of translation and encoding methionine.

Stop Codons

UAA, UAG, UGA are the three stop codons that signal the termination of translation.

Elongation

The step in translation where amino acids are added to the growing polypeptide chain.

Termination

The final step in translation where the newly synthesized polypeptide is released.

Gene Expression

The process of transcribing and translating DNA instructions into functional proteins.

Regulatory Sequences

DNA segments that control the initiation or inhibition of protein synthesis.

Transcription Factors

Proteins that regulate the transcription of genes by promoting or inhibiting RNA polymerase binding.

Operon

A group of genes transcribed together with a single promoter and operator region in prokaryotes.

Lac Operon

An inducible operon in bacteria, usually turned off, and activated in the presence of lactose.

Mutations

Changes in the DNA sequence that can be positive, negative, or neutral in their effects on proteins.

Genetic Variation

Mutations are the primary source of genetic variation, leading to differences in phenotypes.

Horizontal Gene Transfer

Mechanisms like transformation, transduction, and conjugation that increase genetic diversity in prokaryotes.

Biotechnology

Techniques like electrophoresis, PCR, and DNA sequencing used to analyze and manipulate DNA and RNA.

Natural Selection

The process where certain variations in a population are selected by environmental factors for survival and reproduction.

Fitness

The ability of an organism to produce offspring with beneficial traits, contributing to survival of the fittest.

Adaptations

Traits that enhance an organism's survival and reproduction in a specific environment.

Hardy-Weinberg Equilibrium

A principle stating that allele frequencies in a population remain constant over generations in the absence of evolutionary influences.

Speciation

The process by which new species evolve, often through mechanisms like allopatric and sympatric speciation.

Reproductive Isolation

Mechanisms like prezygotic and postzygotic barriers that prevent interbreeding between different species.

Food chain

Shows direction of nutrient and energy transfer from one organism to another.

Trophic levels

Each organism occupies a different trophic level reflecting energy transfers separated from the producer.

Energy efficiency

The transfer of energy between trophic levels is inefficient, with around 10% efficiency.

Autotrophs

Organisms that capture energy from physical or chemical sources in the environment.

Heterotrophs

Organisms that capture energy present in carbon compounds produced by other organisms.

Reproductive strategies

Organisms use various strategies in response to energy availability for reproduction.

Population ecology

Study of populations, interactions, adaptations, and factors affecting growth.

Density-dependent factors

Factors whose effect on population size relies on population density.

Density-independent factors

Factors that affect population size regardless of population density.

Logistic growth model

Describes population growth starting slowly, followed by exponential growth, and stabilizing.

Carrying capacity

Maximum population size an environment can sustain.

Community ecology

Study of species interactions, diversity, and composition in a community.

Species diversity

Variety of species and quantity of individuals in each species.

Species composition

Refers to the identity of each species in a community.

Interactions

Relationships among populations affecting energy and matter access.

Biodiversity

Ecosystem diversity related to resilience, abiotic, and biotic factors maintaining diversity.

Keystone species

Species crucial for community structure; their removal can lead to ecosystem collapse.

Invasive species

Non-native species that harm the community they are introduced to.

Evolution

Change in genetic makeup of a population over time.

Disruptions to ecosystems

Changes due to human activities, invasive species, and geological or meteorological activities.