AP BIO Final Review

Units 1-8

Natural Selection

The process where organisms with traits better suited to their environment survive and reproduce more

Evolution

The change in species over time

Evolutionary Fitness

An organism's ability to survive and reproduce

Selective Pressure

A factor that influences which traits are beneficial

Speciation

The formation of a new species

Reproductive Isolation

When two populations can no longer mate and produce fertile offspring

Allopatric

Speciation caused by geographic separation

Sympatric

Speciation that occurs without physical separation

Divergent Evolution

When related species evolve different traits

Nonrandom Mating

Mating that is influenced by traits, not random chance

Adaptive Radiation

One species evolving into many different forms to fit different environments

Extinction

When a species no longer exists

Species Diversity

The variety of species in an area

Ecosystems

Communities of living things and their physical environment

Niche

The role or job of an organism in its environment

RNA World Hypothesis

The idea that RNA was the first genetic material before DNA

Convergent Evolution

When unrelated species evolve similar traits

Mutation

A change in DNA

Population

A group of the same species living in the same area

Genetic Drift

Random changes in gene frequency in a small population

Bottleneck Effect

A sharp reduction in population size that changes gene frequencies

Founder Effect

Genetic differences in a new population started by a few individuals

Migration

Movement of individuals between populations

Morphology

The study of form and structure of organisms

Hardy-Weinberg Equilibrium

A condition where a population's allele frequencies do not change

Fossil

Remains or traces of ancient organisms

Vestigial Structure

A structure that has lost its original function

Phylogeny

The evolutionary history of a species or group

Cladogram

A diagram showing evolutionary relationships based on shared traits

Phylogenetic Tree

A diagram showing common ancestry and evolution over time

Molecular Clock

A method of estimating evolutionary time using mutation rates

Out-Group

A species or group used for comparison in a phylogenetic tree

Lineage

A sequence of species that descend from a common ancestor

Atom

The smallest unit of matter that retains the properties of an element

Hydrogen Bond

A weak attraction between a slightly positive hydrogen atom and another negative atom

Adhesion

Water sticking to other substances

Cohesion

Water molecules sticking to each other

Polar

Having an uneven distribution of charge (like water)

Surface Tension

The tightness across the surface of water caused by cohesion

Essential Element

An element required for life (like carbon, hydrogen, oxygen, etc)

Macromolecule

A large molecule made of smaller building blocks (like proteins or DNA)

Dehydration Synthesis

Joining molecules together by removing water

Nonpolar

A molecule with no charge separation; doesn’t mix with water

Hydrolysis

Breaking a molecule apart by adding water

Monomer

A single building block of a macromolecule

Phospholipids

Fat molecules that make up cell membranes; have hydrophobic and hydrophilic parts

Saturated Fats

Fats with no double bonds; usually solid at room temperature

Unsaturated Fats

Fats with one or more double bonds; usually liquid at room temperature

Deoxyribose

The sugar in DNA

Nitrogenous Base

A molecule in DNA or RNA that pairs with another (A, T, G, C, or U)

Nucleic Acid

A macromolecule made of nucleotides (like DNA or RNA)

Nucleotide

The building block of nucleic acids (sugar + phosphate + base)

Ribonucleic Acid

RNA; a single-stranded nucleic acid that helps in making proteins

Ribose

The sugar in RNA

Carbohydrates

Macromolecules used for quick energy and structure; made of sugar units

Deoxyribonucleic Acid (DNA)

A molecule that stores genetic information

Lipid

A macromolecule used for long-term energy storage and cell membranes

Phosphate

A group containing phosphorus and oxygen; part of nucleotides and phospholipids

Polymer

A long molecule made of many monomers

Protein

A macromolecule made of amino acids; does most of the work in cells

Amino Acid

The building block of proteins

Amino Terminus

The end of a protein chain with an amino group

Carboxyl Terminus

The end of a protein chain with a carboxyl group

R group

The variable side chain of an amino acid that determines its properties

Hydrophilic

Water-loving; dissolves in water

Hydrophobic

Water-fearing; does not dissolve in water

Covalent Bond

A strong bond where atoms share electrons

Synthesis

The process of building larger molecules from smaller ones

3’5’-Antiparallel

The opposite direction of DNA strands; one runs 3' to 5', the other 5' to 3'

Double Helix

The twisted ladder shape of DNA

Subunit

A single part of a larger complex or molecule

Alpha Helix

A coiled structure in proteins (a type of secondary structure)

Beta-Sheet

A folded, sheet-like structure in proteins (a type of secondary structure)

Peptide

A short chain of amino acids

Polypeptide

A long chain of amino acids that makes up proteins

Primary Structure

The order of amino acids in a protein

Secondary Structure

Protein folding into alpha helices or beta-sheets

Tertiary Structure

The overall 3D shape of a protein

Sugar-Phosphate Backbone

The repeating chain of sugar and phosphate in DNA/RNA

Carbohydrate

A sugar or chain of sugars used for energy and structure

Protein

A macromolecule that performs many functions in cells, made of amino acids

Cell Theory

All organisms are composed of one or more cells, and all cells arise from pre-existing cells

Prokaryotic cells include

Bacteria and archaea

Prokaryotic Cell

No nucleus, lack membrane-bound organelles, less complex, and smaller

Eukaryotic cells include

Plants, animals, fungi, and protists

Eukaryotic Cells

Cells that contain a nucleus and membrane-bound organelles and are generally larger and more complex

Ribosome structure:

Made up of two subunits, protein and rRNa

Ribosome function:

Produces proteins based on DNA/RNA sequence

Plasma (cell) membrane structure:

Phospholipid bilayer with embedded proteins

Plasma (cell) membrane function:

Regulates the entry and exit of substances in and out of the cell

Membrane protiens

Aid in regulation

Cytosol structure:

Semifluid solution composed of water and inorganic and organic molecules

Cytosol function:

Hold other organelles in place and the enzymes help aid in chemical reactions

Cytoplasm

The material within a cell membrane, excluding the nucleus, that includes cytosol and organelles

All cell types have a…

Plasma membrane, ribosome, and cytoplasm

Endosymbiotic Theory

Mitochondria and chloroplasts are membrane bound organelles that were engulfed by Eukaryotic cells billions of years ago

Evidence of Endosymbiotic theory

Mitochondira DNA: Circular DNA resembles prokaryotic cells

Evidence of Endosymbiotic theory

Mitochondria/Chloroplast Membrane: Outer membrane from the eukaryotic cell and inner membrane resembling prokaryotic membranes.

Evidence of Endosymbiotic theory

Ribosomes in the Mitochondria: resemble those of prokaryotes

Evidence of Endosymbiotic theory

Mitochondria reproduce similarly as both divide in an asexual fashion similar to binary fission of bacteria