Cell Biology, Genetics & Microbiology – Vocabulary Review

A comprehensive set of vocabulary flashcards covering cell structure, genetics, protein synthesis, macromolecules, inheritance patterns, microbiology, and microscopy concepts from the lecture notes.

Cell

The fundamental unit of life; over 250 different types compose human tissues and organs.

Organelle

Specialized structure within a cell’s cytoplasm that performs a specific function.

Cytoplasm

Gel-like interior of the cell that contains organelles and cytosol.

Golgi apparatus

Organelle that processes, modifies, and packages proteins and lipids for transport.

Lysosome

Digestive vesicle that breaks down waste materials and invading microbes.

Mitochondrion

Organelle that generates ATP, the cell’s chemical energy.

Ribosome

Molecular machine that synthesizes proteins from amino acids.

Rough Endoplasmic Reticulum

ER studded with ribosomes; synthesizes and processes proteins.

Smooth Endoplasmic Reticulum

ER lacking ribosomes; synthesizes lipids and detoxifies chemicals.

Vacuole

Storage organelle for water, nutrients, toxins, or carbohydrates.

Tissue

Group of similar cells performing a common function.

Connective tissue

Tissue that supports, binds, and protects other tissues and organs.

Epithelial tissue

Tissue forming protective sheets that line or cover body surfaces.

Nervous tissue

Tissue specialized for conducting electrical impulses.

Muscular tissue

Tissue capable of contraction to produce movement.

Mitosis

Cell division producing two genetically identical daughter cells for growth and repair.

Interphase

Preparation stage of the cell cycle in which DNA replicates.

Prophase

Mitosis stage where chromatin condenses into visible chromosomes.

Metaphase

Mitosis stage where chromosomes align at the cell’s equator.

Anaphase

Mitosis stage where sister chromatids separate toward opposite poles.

Telophase

Mitosis stage where two nuclei reform before cytokinesis.

Cytokinesis

Division of the cytoplasm resulting in two separate daughter cells.

Meiosis

Two-stage division of germ cells producing four haploid gametes.

Homologous chromosomes

Chromosome pairs carrying the same genes but possibly different alleles.

Prophase I

Meiosis I stage where homologous chromosomes pair and cross over.

Metaphase I

Meiosis I stage where homologous pairs align in the cell center.

Anaphase I

Meiosis I stage where each homolog is pulled to opposite poles.

Telophase I

Meiosis I stage forming two nuclei, each with half the original chromosomes.

Prophase II

Meiosis II stage in haploid cells prepping chromosomes for division again.

Metaphase II

Meiosis II stage where chromosomes line up singly at the equator.

Anaphase II

Meiosis II stage where sister chromatids separate to opposite poles.

Telophase II

Final meiosis stage yielding four haploid daughter cells.

Gamete

Haploid reproductive cell (sperm or egg).

Autotroph

Organism that makes its own food through photosynthesis; self-feeder.

Heterotroph

Organism that obtains nutrients by consuming other organisms.

Prokaryotic cell

Cell lacking a nucleus; characteristic of bacteria and archaea.

Eukaryotic cell

Cell with a membrane-bound nucleus and organelles; found in plants, animals, fungi, protists.

Flagellum

Long whip-like structure used for cell movement in many bacteria.

Capsule (bacterial)

Protective outer layer of polysaccharide surrounding some bacteria.

Fimbriae

Short hair-like bacterial projections that aid attachment to surfaces.

Cell wall

Rigid layer outside plasma membrane; provides support in plants, bacteria, and fungi.

Plasma membrane

Phospholipid bilayer controlling entry and exit of substances in the cell.

Nucleoid region

Area in prokaryotes where circular DNA chromosome is located.

Binary fission

Asexual reproduction method of prokaryotes producing two identical cells.

Chloroplast

Plant organelle where photosynthesis occurs; contains chlorophyll.

Centriole

Cylindrical structure aiding in spindle formation during cell division.

Nucleotide

Monomer of nucleic acids composed of sugar, phosphate, and nitrogenous base.

DNA (Deoxyribonucleic acid)

Double-stranded molecule encoding genetic information; forms a double helix.

Double helix

Twisted-ladder shape of DNA formed by two complementary strands.

RNA (Ribonucleic acid)

Single-stranded nucleic acid involved in protein synthesis.

mRNA (Messenger RNA)

RNA copy of a gene that carries coding information to ribosomes.

rRNA (Ribosomal RNA)

RNA that combines with proteins to form ribosomes’ structural framework.

tRNA (Transfer RNA)

RNA molecule that delivers specific amino acids to the ribosome during translation.

Transcription

Process where DNA is copied into mRNA in the nucleus.

Translation

Process where ribosomes read mRNA to assemble amino acids into a protein.

Codon

Three-nucleotide mRNA sequence specifying one amino acid.

Anticodon

Complementary three-base sequence on tRNA that pairs with an mRNA codon.

Gene

DNA segment containing instructions to make a protein or functional RNA.

Chromosome

Tightly coiled DNA structure carrying genes; humans have 46.

Allele

Different version of the same gene.

Dominant allele

Allele whose trait is expressed whenever present.

Recessive allele

Allele expressed only in homozygous condition.

Genotype

Genetic makeup; specific alleles an organism possesses.

Phenotype

Observable physical or biochemical traits of an organism.

Homozygous

Having two identical alleles for a gene.

Heterozygous

Having two different alleles for a gene.

Mendel’s Law of Segregation

Each offspring receives one allele per gene from each parent.

Law of Dominance

Dominant allele masks expression of a recessive allele in heterozygotes.

Dihybrid cross

Genetic cross tracking inheritance of two traits simultaneously.

Non-Mendelian inheritance

Patterns of inheritance that do not follow simple dominant-recessive rules.

Mutation

Permanent change in DNA nucleotide sequence caused by substitution, insertion, or deletion.

Sense strand

DNA strand carrying genetic code in 5′→3′ direction.

Antisense strand

Complementary DNA strand (3′→5′) used as the template in transcription.

Macromolecule

Large organic polymer such as carbohydrates, lipids, proteins, or nucleic acids.

Monomer

Small subunit that links with others to form a polymer.

Polymer

Large molecule made of repeated monomer units.

Dehydration synthesis

Reaction forming covalent bonds between monomers by removing water.

Hydrolysis

Reaction that breaks covalent bonds between monomers using water, releasing energy.

Carbohydrate

Sugar or starch molecule with general formula CₙH₂ₙOₙ; primary energy source.

Monosaccharide

Single sugar unit, e.g., glucose or fructose.

Disaccharide

Carbohydrate composed of two monosaccharides linked together.

Polysaccharide

Large carbohydrate polymer of many monosaccharide units.

Lipid

Hydrophobic macromolecule including fats, oils, waxes, phospholipids, and steroids.

Fatty acid

Long hydrocarbon chain with a carboxyl group; building block of many lipids.

Phospholipid

Amphipathic lipid forming cell membranes’ bilayer.

Steroid

Lipid with four fused rings acting as chemical messenger (e.g., hormones).

Wax

Hydrophobic lipid used for waterproofing and protection.

Protein

Polymer of amino acids linked by peptide bonds; performs structural and enzymatic roles.

Peptide bond

Covalent bond connecting adjacent amino acids in proteins.

Enzyme

Protein catalyst that speeds chemical reactions by lowering activation energy.

Exergonic reaction

Chemical reaction that releases energy.

Endergonic reaction

Chemical reaction that requires energy input.

Nucleic acid

Polymer of nucleotides; DNA or RNA that stores or transmits genetic information.

Virulence

Degree of pathogenicity or harm caused by a microorganism.

Pathogen

Disease-causing microorganism such as bacteria, virus, fungus, or protozoan.

Protozoan

Single-celled eukaryote that often feeds on other cells; some are parasitic.

Virus

Non-cellular infectious agent with nucleic acid core and protein coat.

Fungi

Eukaryotic organisms (molds, yeast, mushrooms) absorbing nutrients from environment.

Parasite

Organism that lives on or in a host, obtaining nutrients at the host’s expense.

Bacteria

Prokaryotic microorganisms; may be beneficial or pathogenic.