Cell Structure and Membrane Biology (Video)

Vocabulary flashcards covering cell structure, organelles, and membrane basics from the video notes.

Nucleus

Contains DNA and controls cellular activities.

DNA

Molecule that carries the genetic information of the cell.

Prokaryote

Single-celled organism without a true nucleus or membrane-bound organelles.

Eukaryote

Organism with a true nucleus and membrane-bound organelles; usually larger than prokaryotes.

Endomembrane system

Interconnected membranes (nuclear envelope, ER, Golgi, lysosomes, vesicles) that modify, sort, and transport proteins and lipids.

Nuclear envelope

Double membrane surrounding the nucleus with nuclear pores for material exchange.

Nuclear pores

Openings in the nuclear envelope that regulate exchange between the nucleus and cytoplasm.

Endoplasmic Reticulum (ER)

Membrane system involved in protein and lipid synthesis and modification.

Rough Endoplasmic Reticulum (RER)

ER studded with ribosomes; site of protein synthesis and modification.

Smooth Endoplasmic Reticulum (SER)

ER lacking ribosomes; synthesizes lipids, detoxifies chemicals, and stores calcium.

Golgi apparatus

Stacks of flattened sacs that modify, sort, and package proteins and lipids for transport.

Lysosomes

Organelle containing digestive enzymes that break down waste and old cell parts.

Vesicles

Small membrane-bound sacs that transport materials between organelles and to/from the plasma membrane.

Cytoskeleton

Network of filaments (microfilaments, intermediate filaments, microtubules) that provides structure and movement.

Microfilaments

Thin actin filaments that support the cell and aid in movement and muscle contraction.

Intermediate filaments

Filaments that provide mechanical strength and help maintain cell shape.

Microtubules

Thick tubulin filaments that provide tracks for organelle movement and form the mitotic spindle.

Mitochondria

Organelle where cellular respiration occurs and ATP is produced.

Ribosomes

Sites of protein synthesis.

Nucleolus

Region inside the nucleus where ribosomes are produced.

Peroxisomes

Break down fatty acids and detoxify harmful substances.

Centrosome

Organizes microtubules; essential for organizing the spindle during cell division (noting prominence in animal cells).

Chloroplasts

Plant cell organelles where photosynthesis occurs, converting light energy to chemical energy.

Central vacuole

Large storage sac in plant cells that stores water and nutrients and contributes to turgor pressure.

Cell wall

Rigid layer outside the plasma membrane in plants that provides structure and protection.

Plasma membrane

Phospholipid bilayer that regulates movement of substances into and out of the cell.

Plasmodesmata

Channels through plant cell walls that connect adjacent plant cells for transport and signaling.

Cytoplasm

Jelly-like interior where cellular processes occur.

Fluid mosaic model

Membrane model describing a dynamic, fluid phospholipid bilayer with embedded proteins and carbohydrates.

Phospholipid bilayer

Two layers of phospholipids forming the core structure of the cell membrane.

Hydrophobic tails

Phospholipid tails that face inward away from water.

Hydrophilic heads

Phospholipid heads that face aqueous environments on both sides of the membrane.

Integral proteins

Membrane proteins that span the bilayer and assist in transport.

Peripheral proteins

Proteins on the membrane surface involved in signaling and support.

Carbohydrates (glycoproteins and glycolipids)

Carbohydrates attached to proteins or lipids that function in cell recognition and signaling.

Cholesterol

Sterol within the membrane that helps maintain fluidity and stability, especially in animal cells.

Membrane fluidity

Property allowing membrane components to move freely, enabling self-healing and shape changes.