Cell Biology, Molecular Genetics, and Lab Review Flashcards

Vocabulary practice flashcards generated directly from the lecture review and lab review notes covering mitosis, protein synthesis, transport mechanisms, genetics, pH, and microscopy.

Mitosis

The division of the nucleus that produces 2 genetically identical cells.

Early Prophase

The initial phase of mitosis where chromosomes condense and early mitotic spindles begin forming.

Late Prophase

The phase of mitosis where the nuclear envelope breaks apart, spindle fibers attach to kinetochores, and nonkinetochore microtubules interact.

Metaphase

The phase of mitosis where chromosomes align along the metaphase plate in the middle of the cell.

Anaphase

The shortest stage of mitosis, during which sister chromatids split apart into daughter chromosomes and move to opposite poles.

Telophase

The stage of mitosis that begins when chromosome movement stops; spindle disappears, nucleoli reappear, and new nuclear envelopes form.

Cytokinesis

The division of the cytoplasm that forms a cleavage furrow and yields two separate daughter cells.

Transcription

The process occurring within the nucleus where DNA is used as a template to synthesize mRNA, catalyzed by RNA polymerase.

Translation

The process occurring at ribosomes where mRNA codons are read, and tRNA brings amino acids to link them together into a protein.

mRNA

Messenger RNA; carries genetic instructions from DNA in the nucleus to the ribosomes for protein synthesis.

tRNA

Transfer RNA; brings specific amino acids to the ribosomes during translation.

rRNA

Ribosomal RNA; forms structural parts of ribosomes and assists in protein synthesis.

Rough Endoplasmic Reticulum (Rough ER)

An organelle with attached ribosomes where newly synthesized proteins enter for processing and transport.

Golgi Apparatus

An organelle that modifies proteins before they are packaged into vesicles for transport to their final destination.

Extracellular Fluid (ECF)

Fluid surrounding the outside of cells containing water, ions, nutrients, hormones, and waste.

Extracellular Matrix (ECM)

Substance outside the cell providing structural support, composed of proteins secreted by cells.

Cellular Secretions

Materials synthesized and released by cells into the extracellular environment, such as digestive enzymes.

Plasma Membrane

A thin boundary surrounding the cell composed primarily of a phospholipid bilayer with embedded proteins, cholesterol, and carbohydrates.

Tight Junctions

Cell junctions that seal spaces between adjacent cells to prevent molecules from leaking between them.

Desmosomes

Cell junctions that anchor cells firmly together so they do not pull apart under mechanical strain.

Gap Junctions

Cell junctions creating open channels between adjacent cells, allowing direct passage of small molecules and ions for cell communication.

Reception

The first step in cell-to-cell signaling where a signaling molecule (ligand) binds to a specific receptor.

Transduction

The second step in cell signaling where the signal is relayed through the cell using relay proteins or secondary messengers.

Response

The final stage of cell signaling where the cell performs an action, such as activating an enzyme or modifying gene activity.

Facilitated Diffusion

The passive movement of larger, polar, or charged substances across a membrane from high to low concentration using a membrane protein without ATP.

Channel Proteins

Membrane proteins that form open passageways through the lipid bilayer to allow specific ions or water (via aquaporins) to pass.

Carrier Proteins

Membrane proteins that bind to a specific molecule (such as glucose or amino acids) and undergo a conformational shape change to move it across the membrane.

Tonicity

A property describing how a surrounding solution affects the movement of water across a cell membrane, driving water toward higher solute concentration.

Osmotic Pressure

The pressure associated with water moving across a selectively permeable membrane due to differences in solute concentration.

Isotonic Solution

A solution with the same effective solute concentration inside and outside the cell, resulting in zero net water movement and no change in cell size.

Hypotonic Solution

A solution with a lower solute concentration outside the cell than inside, causing water to move into the cell so that it swells.

Hypertonic Solution

A solution with a higher solute concentration outside the cell than inside, causing water to move out of the cell so that it shrinks.

Active Transport

The movement of substances across a membrane against their concentration gradient, requiring energy in the form of ATP (e.g., $\text{Na}^+/\text{K}^+$ pump).

Endocytosis

A form of vesicular transport that brings large substances into the cell.

Exocytosis

A form of vesicular transport that releases materials out of the cell.

Phagocytosis

A type of endocytosis commonly described as cell eating.

T.H. Morgan Group

Researchers who demonstrated that genes are physically located on chromosomes.

Hershey and Chase

Scientists who demonstrated that DNA is the genetic material of the T2 phage.

Watson and Crick

Scientists who discovered the double helix structure of DNA.

Chargaff's Rules

Base-pairing rules in double-stranded DNA stating that Adenine pairs with Thymine ($\text{A}=\text{T}$) and Cytosine pairs with Guanine ($\text{C}=\text{G}$).

Proofreading

The action by DNA polymerase to check newly added bases and remove incorrect nucleotides during DNA replication.

Nuclease Enzyme

An enzyme involved in DNA repair that cuts out damaged DNA segments so they can be replaced.

DNA Ligase

An enzyme that acts as molecular glue to join strands of DNA during replication and repair.

Telomeres

Protective DNA nucleotide sequences located at the terminal ends of chromosomes.

Telomerase

An enzyme capable of extending the length of telomeres at the ends of chromosomes.

pH

A measure of hydrogen ion ($\text{H}^+$) concentration in a solution; $1\text{ pH unit}$ represents a $10\times$ change in $\text{H}^+$ concentration.

Buffer

A chemical solution or stabilizer that resists sudden changes in pH when acids or bases are added.

Strong Acid/Base

An acid or base that dissociates almost completely in water.

Weak Acid/Base

An acid or base that only partially reacts or dissociates in water.

Scanning Lens

The $4\times$ objective lens on a microscope used to locate specimens, yielding a total magnification of $40\times$.

Field of View

The area seen through the microscope lens, which decreases as objective magnification increases ($\text{magnification} \rightarrow \text{field of view}$).

Working Distance

The distance between the objective lens and the specimen slide, which decreases as objective magnification increases ($\text{magnification} \rightarrow \text{working distance}$).