Cell Biology and Transport Lecture Notes

Vocabulary flashcards covering cell structure, organelles, transport mechanisms, tonicity, biomolecules, and chemical reactions.

Cell Theory

A foundational biological concept stating that all living things are made of cells, cells are the basic unit of life, and all cells come from preexisting cells.

Prokaryotic Cells

Cells that have no nucleus and no membrane-bound organelles, are usually smaller, and include Bacteria and Archaea.

Eukaryotic Cells

Cells that have a nucleus and membrane-bound organelles, are usually larger, and include animals, plants, fungi, and protists.

Nucleus

An organelle that stores DNA and controls cell activities.

Nucleolus

A structure inside the nucleus that produces ribosome components.

Ribosomes

Organelles that make proteins.

Rough ER

Endoplasmic reticulum that has ribosomes attached and helps make and process proteins.

Smooth ER

Endoplasmic reticulum that makes lipids and helps detoxify substances.

Golgi apparatus

An organelle that modifies, sorts, and packages proteins and lipids.

Mitochondria

Organelles that produce ATP and serve as the site of cellular respiration.

Lysosomes

Organelles that digest waste and damaged cell parts.

Vacuoles

Organelles that store water, nutrients, or waste.

Cytoskeleton

A structure that provides shape and support to the cell and helps with movement.

Chloroplasts

Organelles found in plants that perform photosynthesis.

Cell wall

A structure found in plants and many other organisms that provides support and protection.

Plant Cells vs. Animal Cells

Plant cells have a cell wall, chloroplasts, and a large central vacuole, while animal cells lack cell walls and chloroplasts; both share cell membranes, nuclei, mitochondria, ribosomes, ER, and Golgi apparatus.

Cell Membrane

A selectively permeable structure made mainly of a phospholipid bilayer containing phospholipids, proteins, cholesterol, and carbohydrates, described by the fluid mosaic model.

Selectively Permeable

A property of a membrane that allows some substances through while restricting others.

Phospholipid Structure

A lipid molecule with a hydrophilic head that faces water and hydrophobic tails that face inward.

Passive Transport

Movement of substances down their concentration gradient (usually high concentration to low concentration) that does not require ATP; includes diffusion, osmosis, and facilitated diffusion.

Diffusion

The movement of particles from high concentration to low concentration until equilibrium is reached; faster with higher temperature, greater concentration gradient, or smaller molecules.

Osmosis

The diffusion of water across a selectively permeable membrane toward the side with higher solute concentration (lower water concentration).

Facilitated Diffusion

A type of passive transport that uses membrane proteins to help substances cross the membrane without requiring ATP.

Isotonic

A condition with equal solute concentration inside and outside the cell, resulting in no net water movement.

Hypotonic

A condition with a lower solute concentration outside the cell, causing water to move into the cell and potentially causing animal cells to swell.

Hypertonic

A condition with a higher solute concentration outside the cell, causing water to move out of the cell and animal cells to shrink.

Active Transport

Movement of substances against the concentration gradient (low concentration to high concentration) that requires energy, usually ATP; examples include protein pumps, endocytosis, and exocytosis.

Endocytosis

A form of active transport that brings material into the cell using vesicles.

Exocytosis

A form of active transport that releases material from the cell using vesicles.

ATP

The main energy currency of the cell that stores usable energy in phosphate bonds and is used for active transport and movement.

Denaturation

The process where a protein loses its normal shape and function due to factors such as heat or extreme pH.

Nucleic Acids

Biomolecules including DNA and RNA whose monomer is a nucleotide.

Nucleotide

The monomer of nucleic acids, composed of a sugar, a phosphate group, and a nitrogenous base.

DNA

A nucleic acid that stores genetic information.

RNA

A nucleic acid that helps use genetic information to make proteins.

Dehydration Synthesis

A chemical reaction that builds larger molecules by joining monomers together and removing water.

Hydrolysis

A chemical reaction that breaks larger molecules apart by adding water.