Chapter 3: Cell Structure and Function

Vocabulary practice flashcards covering cell structure, organelles, membrane transport mechanisms, gene expression, and the cell cycle.

Plasma Membrane

A semi-permeable lipid bilayer composed of hydrophilic heads, hydrophobic tails, glycoproteins, glycolipids, and cholesterol that separates the intracellular environment from the outside.

Microtubules

Cytoskeletal components that hold the shape of the cell and act as train tracks for organelle movement.

Intermediate Filaments

Cytoskeletal elements responsible for cell-to-cell junctions involved in tissue development.

Nuclear Envelope

A double membrane structure that surrounds and contains DNA, remaining continuous with the endoplasmic reticulum.

Nuclear Pores

Openings within the nuclear envelope that regulate the passage of specific proteins into the nucleus.

Chromatin

The nuclear complex of DNA and proteins that condenses to form chromosomes.

Nucleoli

Structures located within the nucleus where ribosomal RNA (rRNA) is synthesized.

Ribosomes

Organelles consisting of a small subunit and a large subunit that read mRNA to carry out protein synthesis.

Rough Endoplasmic Reticulum

A membrane network studded with ribosomes facing the cytoplasm, continuous with the nuclear envelope, which produces finished protein products.

Smooth Endoplasmic Reticulum

An endoplasmic reticulum lacking ribosomes that functions in lipid synthesis, calcium storage, and intracellular transport.

Golgi Apparatus

An organelle responsible for processing, packaging, and secreting cellular products using enzymes to regulate proteins and lipids.

Lysosomes

Enzyme-containing vesicles formed by the Golgi Apparatus that digest cellular debris, support immunity via phagocytosis, and perform autodigestion.

Peroxisomes

Organelles abundant in liver and kidney cells that contain specialized enzymes to detoxify substances and break down fats.

Mitochondria

Double-membrane organelles containing inner folded cristae and a matrix that perform cellular respiration to synthesize ATP using oxygen and carbohydrates.

Osmosis

The passive transport of water across a semi-permeable membrane caused by an unequal concentration of water on either side of the cell membrane.

Facilitated Diffusion

Passive transport of solutes such as glucose or amino acids down their concentration gradient using channel or carrier proteins without ATP consumption.

Filtration

A passive movement mechanism where hydrostatic blood pressure forces liquid, water, and dissolved solutes from high pressure to low pressure areas.

Active Transport

The ATP-dependent movement of molecules against their concentration gradient (from low to high concentration) utilizing membrane protein pumps.

Phagocytosis

A form of endocytosis commonly called 'cell eating,' in which a cell engulfs large particles into an intracellular vacuole for immune support or destruction.

Pinocytosis

A specialized form of endocytosis commonly referred to as 'cell drinking,' where fluid droplets are internalized inside vesicles.

Exocytosis

An active transport process in which intracellular vesicles fuse with the plasma membrane to release contents outside the cell.

Interphase - $G_1$ Phase

The growth phase of interphase where the cell enlarges, doubles its organelles, executes protein synthesis, and performs standard metabolic duties.

Interphase - S Phase

The synthesis phase of interphase in which DNA replication occurs, duplicating a single DNA strand into two identical sister chromatids.

Interphase - $G_2$ Phase

The phase of interphase where the cell synthesizes proteins for cell division, replicates centrioles, and completes final preparations for division.

Transcription

The synthesis process taking place inside the nucleus where DNA serves as a template to form messenger RNA (mRNA).

Translation

The protein synthesis process occurring outside the nucleus where mRNA, tRNA, and rRNA interact on a ribosome to build polypeptide chains.

Mitosis

The nuclear division process that splits one parent cell into two genetically identical daughter cells to maintain chromosome number for growth and tissue repair.

Prophase

The initial stage of mitosis where the nucleolus disappears, chromatin condenses into visible duplicated chromosomes, centrosomes separate, and spindle fibers form.

Metaphase

The mitotic stage during which centromeres of duplicated chromosomes align along the equator of the fully assembled mitotic spindle.

Anaphase

The mitotic stage in which sister chromatids separate into daughter chromosomes and migrate toward opposite spindle poles.

Telophase

The final stage of mitosis in which nuclear envelopes and nucleoli reform around two new nuclei, and chromosomes uncoil back into indistinct chromatin.