Cell Structure and Functions

Vocabulary flashcards covering the major cell components and their functions as presented in the lecture.

Cell

The basic unit of life; all cells are bounded by a plasma membrane, contain cytosol, chromosomes, and ribosomes.

Plasma (Cell) Membrane

Double-layered outer boundary that controls the movement of substances into and out of the cell.

Cytosol

The semi-fluid substance inside the cell in which organelles are suspended.

Chromosome

DNA-containing structure that carries genetic information in the cell.

Ribosome

Organelle responsible for protein synthesis; may be free in cytoplasm or bound to rough ER.

Nucleus

Largest organelle; genetic library and control center containing most of the cell’s genes.

Nuclear Membrane (Nuclear Envelope)

Double membrane that surrounds the nucleus; nuclear pores regulate material exchange.

Nucleolus

Dense region inside the nucleus that contains rRNA and assembles ribosome subunits.

Cytoplasm

Gel-like mixture between plasma membrane and nucleus that houses organelles and hereditary material.

Mitochondrion

Powerhouse of the cell; site of cellular respiration and chemical energy conversion.

Endoplasmic Reticulum (ER)

Network of folded membranes acting as intracellular transport channels.

Rough Endoplasmic Reticulum (Rough ER)

ER studded with ribosomes; mainly involved in protein transport.

Smooth Endoplasmic Reticulum (Smooth ER)

ER without ribosomes; primarily transports lipids and performs detoxification.

Golgi Apparatus

Organelle that manufactures, processes, and packages macromolecules; the cell’s shipping and receiving center.

Lysosome

Membrane sac containing digestive enzymes; breaks down bacteria, foreign material, and worn-out organelles (suicidal bag).

Vacuole

Membrane-bound sac used for storage, digestion, and waste removal; large central vacuole helps plants maintain shape.

Chloroplast

Organelle found in plants and algae; site of photosynthesis containing green pigment chlorophyll.

Cell Wall

Rigid outer layer outside the plasma membrane that provides shape, strength, and protection, and prevents desiccation.

Plant Cell Wall

Cell wall type composed mainly of cellulose fibers embedded in other polysaccharides and proteins.

Fungal Cell Wall

Cell wall type made chiefly of chitin and glucans.

Bacterial Cell Wall

Cell wall type consisting primarily of peptidoglycan.

Plant Cell

Eukaryotic cell characterized by a cell wall, chloroplasts, and a large central vacuole.

Animal Cell

Eukaryotic cell lacking a cell wall and chloroplasts; typically has a smaller vacuole and other specialized structures.

Organelle

Specialized sub-unit within a cell that performs a specific function, e.g., mitochondria, ER, Golgi apparatus.