Cell Biology: Cell Theory, Organelles, Cell Division, and Transport

Comprehensive vocabulary flashcards covering modern cell theory, cell types, organelle structures and functions, interphase, the stages of mitosis and cytokinesis, meiosis stages, cellular transport mechanisms, and essential cell biology terms.

Prokaryotic

Bacteria cells

Eukaryotic

Animal (including human), plant, fungi, and protist cells

Cell (plasma) membrane

Semi-permeable phospholipid bilayer enclosing the cell; controls what enters and leaves, separates extracellular from intracellular fluid.

Cytoplasm

Watery interior containing cytosol, organelles, and inclusions.

Cytosol

Gooey, semi-transparent fluid suspending other cell elements.

Inclusions

Store nutrients, secretory products, and colored particles.

Nucleus

Contains chromosomes and genetic information; surrounded by nuclear membrane (organelle containing chromosomes).

Nucleoplasm

Gel-like fluid inside the nucleus.

Nucleolus

Synthesizes and stores ribosomal RNA; nuclear structure involved with ribosomal RNA.

Chromosomes / DNA

Chromosomes contain genes made of DNA; carry hereditary information.

Rough ER

Ribosome-covered portion of the ER; ER supports intracellular transport, storage, synthesis, and packaging.

Smooth ER

ER without attached ribosomes; part of the cell's transport, storage, synthesis, and packaging network.

Ribosomes

Assemble proteins according to messenger RNA instructions.

Golgi complex / apparatus

Stacked flattened sacs; packages released proteins, aids lipid secretion, and helps break down carbohydrates.

Mitochondria

Double-membraned "powerhouse"; produces ATP, the cell's energy source. Inner membrane folds are cristae.

Lysosomes

Contain digestive enzymes; digest worn-out organelles, food particles, and engulfed pathogens; fuse with vacuoles.

Vacuoles

Storage bubbles holding food, nutrients, or waste products.

Centrosomes

Dense areas near nucleus that contain centrioles and participate in division.

Centrioles

Paired perpendicular cylinders made of microtubules; function in cell division.

Cilia

Short, numerous hairlike projections that move particles across a surface or help cells move through liquid.

Flagellum / flagella

Motile projection used in locomotion; among human cells, sperm cells have flagella.

Cytoskeleton

Labeled in the PowerPoint cell model (slide 8); the slides do not give a separate function description.

Peroxisomes

Labeled in the PowerPoint cell model (slides 8 and 18); no detailed function supplied in the slide text.

G1 Phase

Normal biochemical activity: growth and energy production.

S Phase

DNA replication.

G2 Phase

Synthesis of proteins needed for cell division.

Chromatid

One of two identical DNA strands making up a duplicated chromosome.

Prophase (Mitosis)

Chromosomes become visible; nuclear membrane breaks down; centrosomes move apart and a spindle forms (late prophase may be called prometaphase).

Metaphase (Mitosis)

Chromosomes line up at the metaphase plate in the cell center.

Anaphase (Mitosis)

Duplicated chromatids separate; daughter chromosomes move toward opposite poles.

Telophase (Mitosis)

Spindle breaks down; chromosomes unravel; nuclei look like interphase.

Cytokinesis

Cytoplasm divides into two daughter cells; cell membrane furrows inward, beginning in anaphase and continuing through telophase.

Prophase I

Duplicated chromatin condenses; chromosomes have two sister chromatids.

Metaphase I

Homologous chromosomes line up at cell center.

Anaphase I

Homologous pairs separate; sister chromatids remain together.

Telophase I

Two daughter cells form, each with one chromosome of each homologous pair.

Prophase II

DNA is not replicated again.

Metaphase II

Chromosomes align in the middle.

Anaphase II

Centromeres divide; sister chromatids move separately to the poles.

Telophase II

Four haploid daughter cells result; division is complete.

Mitosis (Cell type / Result)

Body cells / Two genetically identical cells.

Meiosis (Cell type / Result)

Sex cells (eggs and sperm) / Four haploid cells.

Diffusion

No energy required; particles spread high $\rightarrow$ low concentration until equilibrium.

Osmosis

No energy required; water crosses a semi-permeable membrane toward higher solute concentration.

Facilitated diffusion

No energy required; transport proteins help ions/molecules move down a gradient (high $\rightarrow$ low).

Active transport

Yes, energy required; protein pumps move substances, including against their concentration gradient (low $\rightarrow$ high).

Hypertonic Solution

Higher solute concentration relative to cell; cell shrivels.

Isotonic Solution

Same solute concentration; water diffuses in and out naturally.

Hypotonic Solution

Lower solute concentration relative to cell; cell expands and may burst.

Cell theory

Living organisms consist of cells; cells are basic life units; existing cells produce cells.

Organelle

Specialized cell structure with a specific function.

Semi-permeable

Allows some particles, not others, to pass.

Phospholipid bilayer

Two-layer lipid structure making up the cell membrane.

DNA

Deoxyribonucleic acid; carries genetic information.

RNA

Ribonucleic acid; used in protein manufacture.

ATP

Primary chemical energy source for a cell.

Cristae

Folds of the inner mitochondrial membrane.

Haploid

Having one-half the needed chromosomes.

Equilibrium

Balanced concentration reached through diffusion.