Biology Study Guide BIO.1A - BIO.5.7

Comprehensive vocabulary flashcards covering basic biology principles including life characteristics, cell theory, macromolecules, organelles, transport, genetics, evolution, and ecology based on the lecture transcript.

Metabolism

The process by which all living things obtain energy.

Homeostasis

The maintenance of a fairly stable internal environment by living things.

Hook

The first person to name and observe living cells through a microscope.

Schleiden

Scientist who concluded that all plants are composed of cells.

Schwann

Scientist who concluded that all animals are composed of cells.

Virchow

Scientist who stated that all cells come from pre-existing cells.

Bacteriophage

A virus that attaches to a bacterium and destroys or lyses the cell to release more phage particles.

Organic Compounds

Compounds that contain carbon and are found in all living things.

Carbohydrates

Organic molecules made of carbon, hydrogen, and oxygen with a $1:2:1$ ratio; they serve as a major source of energy.

Monosaccharide

The monomer of carbohydrates.

Nucleotide

The monomer of nucleic acids, consisting of carbon, hydrogen, oxygen, nitrogen, and phosphorus.

Proteins

Nitrogen-containing compounds made up of chains of $20$ different amino acids.

Polypeptide

The polymer form of proteins.

Lipids

Water-insoluble organic molecules composed of glycerol and fatty acids used for insulation and energy storage.

Enzymes

Special proteins that regulate biochemical reactions using a lock and key mechanism specific to a substrate.

Active Site

The specific location on an enzyme where a substrate binds.

Nucleolus

A structure inside the nucleus that creates ribosomes.

Ribosomes

Organelles that synthesize proteins; found on the rough endoplasmic reticulum or floating in the cytoplasm.

Smooth Endoplasmic Reticulum

Organelle that helps make lipids and transports nutrients inside the cell.

Golgi Apparatus

Organelle that prepares and packages protein to be imported into or exported out of the cell.

Mitochondria

Known as the powerhouse of the cell, it makes energy in the form of $ATP$.

Chloroplast

Organelle in plant cells that captures solar energy to create food (glucose).

Cytoskeleton

A network of protein fibers that helps give the cell its shape.

Plasma Membrane

A phospholipid bilayer that protects the cell and controls what enters and exits.

Prokaryote

A simple cell structure without a membrane-bound nucleus or membrane-bound organelles; found in bacteria.

Eukaryote

A cell containing a clearly defined nucleus and membrane-bound organelles; found in plants, animals, fungi, and protists.

Capsid

The protective protein layer that surrounds the genetic material of a virus.

Passive Transport

Movement of substances across the plasma membrane without the use of energy, moving with the concentration gradient.

Osmosis

The diffusion of water across the plasma membrane from high to low concentration.

Facilitated Transport

Passive transport where a carrier molecule helps a substance move across the membrane following the gradient.

Active Transport

Movement of substances across the plasma membrane against the concentration gradient (low to high) using energy and carrier molecules.

Endocytosis

An active transport process where large particles are brought into the cell.

Sodium-Potassium Pump

Uses $ATP$ to move three sodium ions out of the cell and two potassium ions into the cell to help transmit nerve impulses.

Hypotonic

A condition where water moves into the cell, causing it to burst or pop.

Hypertonic

A condition where water moves out of the cell, causing it to shrivel.

Isotonic

A condition with no net movement of water, allowing the cell to maintain equilibrium.

Interphase

The longest part of the cell cycle, consisting of $G1$, $S$, and $G2$ phases.

Metaphase

Phase of mitosis where chromosomes meet in the middle of the cell.

Cytokinesis

The final division of the cytoplasm during the cell cycle.

Metastasis

The spread of cancer cells to other parts of the body when they grow aggressively.

Apoptosis

A series of molecular steps leading to programmed cell death used to eliminate unneeded or abnormal cells.

Binary Fission

Asexual reproduction in prokaryotes where the cell splits in two to produce identical daughter cells.

Vegetative Propagation

Plant reproduction where a fragment of a parent plant is used to produce clones.

Autotrophs

Organisms, like plants, that use sunlight to make high-energy carbohydrates (glucose).

Thylakoids

Saclike photosynthetic membranes arranged in stacks within the chloroplast.

Calvin Cycle

Also known as light-independent reactions; occurs in the stroma and uses $ATP$ and $NADPH$ to build stable high-energy sugars.

Aerobic Respiration

The process that releases energy from food in the presence of oxygen, producing about $36 ext{-} 38$ molecules of $ATP$.

Fermentation

A type of anaerobic respiration that releases energy from food without oxygen, producing only $2$ molecules of $ATP$.

Lactic Acid Fermentation

Process in humans during brief periods without oxygen where pyruvic acid and $NADH$ produce lactic acid and $NAD^+$.

Haploid

Cells, such as gametes, that contain half the normal number of chromosomes ($n = 23$).

Crossing Over

The regular exchange of genes between chromosomes during meiosis that leads to greater genetic variation.

Nondisjunction

An error in meiosis where homologous pairs fail to separate, resulting in sex cells with extra or missing chromosomes.

Karyotype

A chart of metaphase chromosome pairs used to study chromosome numbers and identify diseases.

Klinefelter Syndrome

A chromosomal abnormality characterized by an $XXY$ genotype in males.

Turner Syndrome

A chromosomal abnormality characterized by an $XO$ genotype in females.

Heterozygous

A genotype where the two alleles of a pair are different (e.g., $Bb$); often called a hybrid.

Phenotype

The physical appearance or visible description of an organism based on its letters.

Incomplete Dominance

Inheritance pattern where one allele is not completely dominant over another, resulting in a blend of traits.

Codominance

Inheritance pattern where both alleles are expressed simultaneously, such as speckled feathers in chickens.

Codon

A sequence of three nucleotide bases on $mRNA$ that represents the code for one amino acid.

Speciation

The formation of a new species that occurs when members of populations can no longer interbreed.

Adaptive Radiation

The rapid divergence of a single species into several distinct species, often seen in isolated island populations.

Nitrogen Fixation

The conversion of atmospheric nitrogen ($N_2$) into ammonium ($NH_4^+$) for use in organic compounds like amino acids.

Mimicry

A survival tactic where an animal tries to look like another animal to deter predators.

Carrying Capacity

The maximum number of organisms that can be supported in a given environment.

Primary Succession

Ecological changes occurring in an ecosystem that has no soil, such as after a glacier or volcano.

Pioneer Species

The first organisms, such as lichen, to live in an ecosystem during succession.