Week 2: Organelles, Movement of Molecules, Cell Cycle, Diffusion & Osmosis, Tonicity

Vocabulary flashcards covering major organelles, diffusion/osmosis concepts, tonicity, and cell cycle stages from Week 2 notes.

Cytoplasm

Semifluid matrix outside the nucleus that contains organelles.

Cytoskeleton

Maintains cell shape and assists movement of cell parts.

Microtubules

Cylinders of protein molecules present in cytoplasm, centrioles, cilia, and flagella.

Intermediate filaments

Protein fibers that provide support and strength.

Actin filaments

Protein fibers that play a role in movement of the cell and organelles.

Centrioles

Short cylinders of microtubules (function is unknown).

Centrosome

Microtubule organizing center that contains a pair of centrioles.

Lysosome

Vesicle that digests macromolecules and even cell parts; not in plant cells.

Vesicle

Membrane-bounded sac that stores and transports substances.

Nucleus

Organelles that houses the cell’s genetic material and coordinates activities; surrounded by a nuclear envelope.

Nuclear envelope

Double membrane with nuclear pores that encloses the nucleus.

Chromatin

Diffuse threads containing DNA and protein.

Nucleolus

Region that produces subunits of ribosomes.

Endoplasmic Reticulum

Network of membranous sacs; Rough ER has ribosomes, Smooth ER lacks ribosomes and synthesizes lipids.

Rough ER

ER studded with ribosomes; site of protein synthesis.

Smooth ER

ER lacking ribosomes; synthesizes lipid molecules.

Ribosomes

Particles that carry out protein synthesis.

Polyribosome

String of ribosomes simultaneously synthesizing the same protein.

Peroxisome

Vesicle with various functions; breaks down fatty acids and converts hydrogen peroxide to water.

Mitochondrion

Organelle that carries out cellular respiration, producing ATP.

Golgi apparatus

Processes, packages, and secretes modified cell products; not in plant cells.

Endoplasmic Reticulum (general)

System of interconnected membranes involved in synthesis and transport of proteins and lipids.

Diffusion

Movement of solute from an area of high concentration to low concentration.

Osmosis

Diffusion of water across a semipermeable membrane.

Semipermeable membrane

Membrane that allows some substances to pass while blocking others.

Solute

Particles dissolved in a solvent (e.g., sugar, NaCl).

Solvent

The liquid that dissolves solutes (commonly water).

Isotonic

Solution with equal solute concentration inside and outside the cell; no net water movement.

Hypotonic

Outside solution has lower solute concentration; water enters the cell.

Hypertonic

Outside solution has higher solute concentration; water leaves the cell.

Tonicity

Relative concentration of solute/solvent between inside and outside the cell; affects water movement.

Interphase

Cell cycle phase: G1, S, and G2; cell growth and DNA replication.

G1

First gap phase; cell growth.

S phase

DNA synthesis/replication phase.

G2

Second gap phase; preparation for mitosis.

Mitosis (M)

Cell division phase consisting of Prophase, Prometaphase, Metaphase, Anaphase, Telophase; followed by Cytokinesis.

Prophase

Chromosomes condense, spindle forms; nuclear envelope breaks down.

Prometaphase

Nuclear envelope breaks down; spindle attaches to chromosomes.

Metaphase

Chromosomes align at the cell's equator.

Anaphase

Sister chromatids separate and move to opposite poles.

Telophase

New nuclei form; chromosomes de-condense.

Cytokinesis

Division of the cytoplasm resulting in two daughter cells.