Biology Test: Cells, Membrane & Transport Vocabulary

Vocabulary flashcards generated from lecture notes on cell organelles, membrane transport mechanisms, and solution tonicity.

Phospholipid bilayer

A 2-layered cell membrane structure where each phospholipid has a hydrophilic (water-loving) head and a hydrophobic (water-fearing) tail.

Hydrophilic

Water-loving.

Hydrophobic

Water-fearing.

Cell membrane

Controls what enters and leaves the cell; contains proteins that act as receptors, carriers, and identification markers.

Nucleus

Cell organelle that holds the DNA and controls the cell.

Mitochondria

Organelles that make energy in the form of ATP.

Ribosomes

Cell structures that make proteins.

Rough ER

Endoplasmic reticulum with ribosomes that makes proteins for export.

Smooth ER

Endoplasmic reticulum with no ribosomes that makes lipids/fats.

Golgi apparatus

Organelle that packages and ships proteins.

Lysosomes

Organelles responsible for digestion and cleanup by breaking down waste.

Peroxisomes

Organelles that carry out chemical reactions to break down fats and toxins.

Vesicles

Structures that function in the storage and transport of materials inside the cell.

Cilia

Short and numerous structures that move material across the cell surface.

Flagella

Longer and usually few structures that move the whole cell (e.g., a sperm tail).

Passive transport

Transport across a membrane that needs NO cellular energy, moving substances from high to low concentration; includes simple diffusion, facilitated diffusion, osmosis, and filtration.

Simple diffusion

Process where substances move from high concentration to low concentration straight through the membrane without energy.

Facilitated diffusion

Movement from high to low concentration needing no energy, but using a protein carrier or channel to help substances cross.

Osmosis

The movement of water across a membrane from high water concentration to low water concentration.

Filtration

Movement of substances caused by pressure rather than concentration.

Tonicity

The ability of a solution to cause a cell to gain or lose water, depending on the concentration of solutes compared to the cell.

Hypotonic solution

A solution with low solute outside causing water to move INTO the cell, which makes the cell swell and potentially burst.

Hypertonic solution

A solution with high solute outside causing water to move OUT of the cell, which makes the cell shrink or crenate.

Isotonic solution

A solution in which water moves in and out equally, resulting in no net change in the cell.