Video Notes: Cell Membrane, Nucleus, Endomembrane System, Organelles, and Microtubule Arrangements

Vocabulary flashcards derived from lecture notes (Pages 1–3) covering membrane components, nucleus and chromatin, endomembrane system, organelles, and microtubule arrangements.

Peripheral protein

A protein loosely attached to the membrane surface that assists with signaling, communication, and supporting the cell’s structure.

Integral protein

A protein embedded in the membrane that functions as a transporter, receptor, or anchor.

Transmembrane protein

An integral protein that spans the entire membrane and aids in transport and cell communication.

Phospholipid bilayer

The two-layer structure forming the cell membrane that controls entry and exit and creates a barrier.

Fluid mosaic model

The description of the cell membrane as a flexible, dynamic sea of lipids with various proteins floating within.

Channel protein

A protein that forms a pore in the membrane to allow specific molecules or ions to pass.

Aquaporins

Special channel proteins that facilitate rapid water movement across the membrane.

Cholesterol’s role in the membrane

Cholesterol helps stabilize the membrane, preventing it from becoming too stiff or too fluid.

Glycocalyx

A sugar coating on the outer membrane that protects the cell, aids in recognition, and assists in adhesion.

Nuclear membrane (nuclear envelope)

A double membrane with pores that protects the nucleus and regulates transport into and out of the nucleus.

Chromatin

Uncoiled DNA wrapped around histone proteins; stores genetic information in a usable form.

Chromosome

Condensed, tightly packed DNA that carries genes and is visible during cell division.

Nucleosome

A 'bead' of DNA wrapped around histone proteins; the basic unit of chromatin.

Nucleoli (nucleolus)

Dense region inside the nucleus where ribosomes are made.

Rough endoplasmic reticulum (RER)

ER covered with ribosomes; synthesizes proteins destined for secretion or membranes.

Smooth endoplasmic reticulum (SER)

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

Golgi apparatus

Modifies, sorts, and packages proteins and lipids for transport inside or outside the cell.

Vesicle

Small membrane-bound sac that transports materials within the cell.

Centrioles

Organize microtubules and assist in animal cell division.

Peroxisome

Organelle that breaks down fatty acids and detoxifies harmful molecules using enzymes.

Cytoskeleton

A network of protein fibers (microtubules, microfilaments, intermediate filaments) that provides shape, support, and movement.

Lysosome

Organelle containing digestive enzymes that break down waste, damaged organelles, and invading bacteria.

9+2 microtubule arrangement

Structure of cilia and flagella: nine outer pairs of microtubules with two in the center, used for movement.

9+0 microtubule arrangement

Structure of centrioles and basal bodies: nine triplets around a circle with none in the center, used for organization rather than movement.