Biology-Test2 Vocab

Organelle

A tiny cell structure that carries out a specific function within the cell

cell membrane

A cell structure that controls which substances can enter or leave the cell.

cell wall

A rigid structure that surrounds the cell membrane and provides support to the cell

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

Chloroplast

organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Ribosomes

Makes proteins (protein synthesis)

Vacuole

a space or vesicle within the cytoplasm of a cell, enclosed by a membrane and typically containing fluid.

Golgi body

A structure in a cell that receives proteins and other newly formed materials from the endoplasmic reticulum, packages them, and distributes them to other parts of the cell.

Lysosomes

Uses chemicals to break down food and worn out cell parts

Endoplasmic Reticulum

A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids

active transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

passive transport

Requires NO energy, Movement of molecules from high to low concentration, Moves with the concentration gradient

simple diffusion

- net movement of dissolved particles down their concentration gradient

facilitated diffusion

process of diffusion in which molecules pass across the membrane through cell membrane channels

Homeostasis

relatively constant internal physical and chemical conditions that organisms maintain

Osmosis

diffusion of water across a selectively permeable membrane

Semi-permeable

characteristic of a cell membrane which allows some molecules to pass through but not others

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

Eukaryote

A cell that contains a nucleus and membrane bound organelles

Prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles