Cell Organelles

Cell Theory Basic Unit of Life All organisms are made up of one or more cells and the products of those cells. All cells carry out life activities (require energy, grow, have a limited size) New cells arise only from other living cells by the process of cell division

3 Main Components (All Cells) Plasma Membrane/Cell Membrane Structure- a bi-lipid membraneouos layer composed of proteins and carbohydrates (Fluid like) Function- the cell membrane separates the cell from its external environment, and is selectively permeable. It protects the cell and provides stability Proteins are found embedded within the plasma membrane, with some extending all the way through in order to transport materials Carbohydrates are attached to proteins and lipids on the outer lipid layer

Main Parts con’t Cytoplasm Structure – The jelly-like substance composed of mainly water and found between the cell membrane and nucleus. The cytoplasm makes up most of the “body” of a cell and is constantly streaming Function – Organelles are found here and substances like salts may be dissolved in the cytoplasm.

Main Parts con’t Nucleus Structure – The largest organelle in the cell. Round and surrounded by a double membrane. Has selectively permeable pores. Contains genetic information (DNA) on special strands called chromosomes Function – The control center of the cell, for cell metabolism and reproduction

Individual Organelles Endoplasmic Reticulum (E.R.) Network of canals filled with fluid “Transport system”, carry materials throughout cell Some are Lined with Ribosomes others are not. Ribosomes Small particles found individually in the cytoplasm and E.R. Produce proteins, “Factories” in the cell

Con’t Golgi Body/Apparatus Lysosomes Stacks of flattened membraneous materials “Pancakes” Temporarily stores proteins until they leave cell Lysosomes Small sac-like structures surrounded by single membrane Strong dygestive enzymes are released to break down worn out organelles or food. “Suicide Sac”

Con’t Mitochondria Vacuoles Round “tube-like” organelles with double membrane (Inner highly folded) “Powerhouse” of the cell releases food energy from food molecules in cell. Called Respiration Muscle cells require more energy require more mitochondria Vacuoles Fluid filled enclosed by membrane “Storage facility” of food, water, sugar, minerals, and waste

Features of Plant Cells Cell Wall – Rigid organelle outside the membrane composed of cellulose. Contains pores to allow materials to pass to and from the cell membrane Central Vacuole – Large fluid filled vacuole Plastids – Double membrane organelles. Makes and store food. Found in cytoplasm (2 types) Leucoplasts – colorless store startch and other nutrients (potato startch) Chlorplast – Different colored pigment. Green pigment chlorophyll important in photosynthesis