General Biology – Exam Review Vocabulary

Vocabulary flashcards covering key biological concepts from the lecture’s multiple-choice review questions.

Competition

The ecological interaction in which two or more organisms vie for the same limited resource, such as food or territory.

Semi-conservative DNA replication

Process in which each new DNA molecule consists of one parental (old) strand and one newly synthesized strand.

Gamete DNA mass

Half the amount of DNA found in the diploid mother cell, due to meiosis.

Haploid chromosome number

The number of chromosomes in a gamete, equal to half (n) the diploid (2n) number found in somatic cells.

Mean (average)

A measure of central tendency calculated by dividing the sum of values by the number of values.

Ribosome

Cellular organelle that serves as the site of protein synthesis by translating mRNA into polypeptides.

Mitochondrion

Membrane-bound organelle that produces ATP through aerobic respiration; known as the cell’s powerhouse.

Golgi apparatus

Stack of flattened membranes responsible for modifying, sorting, and packaging proteins and lipids for secretion or delivery to organelles.

Centriole

Microtubule-based structure involved in organizing the mitotic spindle; not a repository of genetic information.

X-linked recessive inheritance (Hemophilia)

Pattern in which a recessive allele on the X chromosome is passed from carrier mothers or affected fathers to offspring; typically affects sons of carrier mothers and all daughters of affected fathers become carriers.

Prokaryotic nucleus absence

Characteristic of organisms like cyanobacteria, which lack a membrane-bound nucleus.

Active transport

Movement of molecules across a membrane against their concentration gradient using energy, usually ATP.

Predation

Ecological relationship in which one organism (predator) feeds on another (prey).

Hypotonic lysis

Bursting of an animal cell when placed in distilled water because water enters the cell osmotically.

Cilium

Short, numerous, hair-like projection composed of microtubules that moves fluid past the cell or propels unicellular organisms.

Plant cell wall

Rigid layer of cellulose surrounding plant cells; absent in animal cells.

RBC hemolysis

The bursting (lysis) of red blood cells in a hypotonic solution such as distilled water.

Lipid

Class of hydrophobic biomolecules that includes fats, oils, and fatty acids.

Transcription

Process in which a segment of DNA is copied into messenger RNA (mRNA) by RNA polymerase.

Translation

Process in which ribosomes use mRNA to assemble amino acids into a polypeptide chain.

Meiosis

Type of cell division that produces four genetically varied haploid gametes from one diploid parent cell.

Diploid number (2n = 30)

Indicates that somatic cells have 30 chromosomes; meiosis will produce gametes with 15 chromosomes each.

Enzyme

Biological catalyst composed primarily of amino acids that speeds up reactions without being consumed.

Stroma

Fluid interior of chloroplasts where the Calvin cycle (light-independent reactions) occurs.

Oxygen (O2)

Final electron acceptor in the electron transport chain of aerobic respiration.

Muscle tissue

Animal tissue type with the highest density of mitochondria due to high ATP demand.

Virus capsid

Protein coat that encloses the genetic material of all viruses.

Ethylene

Plant hormone that promotes fruit ripening and leaf abscission.

Dehydration synthesis (condensation)

Reaction in which two molecules are joined by removing a molecule of water (H2O).

Grana

Stacks of thylakoid membranes inside chloroplasts where the light-dependent reactions of photosynthesis take place.

Cofactor (Iron)

Non-protein helper (often a metal ion) required for the proper functioning of an enzyme.

Glycolysis

Anaerobic metabolic pathway that breaks glucose into pyruvate in the cytoplasm, yielding a small amount of ATP.

Pancreas

Gland that functions as both an endocrine (insulin, glucagon) and exocrine (digestive enzymes) organ.

Oxidation (loss of electron)

Process in which an atom, such as nitrogen becoming N⁺, loses one or more electrons.

Epithelial tissue

Tissue type that covers body surfaces and lines body cavities, forming protective barriers.

Glucose (C6H12O6)

Simple sugar considered an organic compound and primary energy source for cells.

DNA double helix

Two antiparallel strands of nucleotides twisted into a helical structure, as described by Watson and Crick.

Peptide bond

Covalent linkage formed between the amino group of one amino acid and the carboxyl group of another during protein synthesis.

Lysosome

Membrane-bound vesicle containing hydrolytic enzymes; involved in intracellular digestion and apoptosis.

White blood cells (Leukocytes)

Immune cells that include phagocytes and lymphocytes; responsible for defense against pathogens.

Biological membrane composition

Phospholipid bilayer embedded with proteins; common to mitochondria and endoplasmic reticulum membranes.

Closed circulatory system

Circulatory system, found in mammals, in which blood is confined to vessels separate from interstitial fluid.

Endosymbiotic organelle DNA

Mitochondria and chloroplasts possess their own circular DNA, supporting the endosymbiosis theory.

Gas exchange surfaces

Structures like plant stomata and mammalian alveoli that facilitate diffusion of O2 and CO2.

Nondisjunction

Meiotic error in which homologous chromosomes or sister chromatids fail to separate, leading to aneuploid gametes.

Interspecific competition

Competition between individuals of different species, such as lions and hyenas for buffalo prey.

Trophic-level energy loss

Energy diminishes between successive trophic levels through cellular respiration, heat, and waste (e.g., feces).

Plant classification traits

Features such as presence of flowers and seeds used to categorize major plant groups.

Cilia vs. Flagella

Cilia are shorter and more numerous than flagella, which are longer and fewer per cell.

Common ancestry

Theory supported by conserved genes like RNA polymerase across all living species, implying descent from a shared ancestor.

Bacterial transformation (Griffith)

Process by which bacteria uptake external DNA, demonstrated when harmless strains became virulent after exposure to heat-killed virulent strains.

Color-based pollinator preference

Experimental question assessing whether flower color influences the landing behavior of honeybees.

Yeast population growth

Observation that cell density continued to increase beyond 10 hours, refuting the hypothesis that growth would stop.