Introduction to the Cell video (3 min) Chapter 7 Voyage within a Cell 14 min review

History of Cells: video clip 1 video clip 2 Discovery of cells made possible with the discovery of the microscope Def: smallest unit of matter that can carry on all the processes of life

Discovery of the Cell (made possible by the discovery of scope 1665 - Hooke - Discovered and named the cell – observed cork – called them tiny rooms 1673 Leewenhoek - First to see living cells (microscopic organisms)

Discovery of the Cell 1824 – Dutrochet - Plants and Animals are made of cells 1831 - Brown Discovered the nucleus 1835 - Dujardin Discovered protoplasm 1838 - Schleiden (botanist) Hypothesized all plants were made of cells

Discovery of the Cell 1839 - Schwann (zoologist) 1855 - Virchow Hypothesized all animals are made of cells 1855 - Virchow All cells come from other cells Discovered that the nucleus controls the cell

Cell Theory 1. All living things are composed of cells 2. Cells are the basic unit of structure and function in all living things organelles Cell Tissue Organs Organ System Organism 3. Cells come from reproduction of existing cells

Types of Cells Eukaryotic Multicellular and unicellular Prokaryotic Nucleus present Membrane bound organelles Ex: animals, plants, fungus, algae Prokaryotic Unicellular No nucleus No membrane bound organelles Most numerous of living things Ex: bacteria, protista

Cell Shape The shape of the cell (form) reflects its function. Ex: Nerve cell are long strands for sending chemical messages throughout the body. Ex: Blood cells are circular and pliable to get through the blood vessels.

Cell Shape- “Skin Deep”

Cell Size 10-50 um (micrometers) Limited by its surface area to volume ratio

Lipid bilayer Contain a phosphate head that is polar and soluble in water Has a fatty acid tail that is nonpolar and insoluble in water

Parts of the Cell Cell (Plasma) Membrane Semipermeable - keeps some molecules out, but lets others through (controls what enters and leaves cell Made of a lipid bilayer Has protein channels that aid with the movement of nutrients, water, oxygen into the cell and waste and CO2 out of the cell Have carbohydrate chains which are chemical recognition sites and interact with each other

Fluid Mosaic Model Fluid: Membrane bilayer acts as liquid (lipids and proteins move within bilayer) Mosaic: made of several different components Ex’s: nuclei, vacuoles, mitochondria, and chloroplast

Cytoplasm contains water and salts between cell membrane and the nucleus Site of chemical reactions

Nucleus and Nucleolus Nucleus directs all activity of the cell; such as cell growth, protein synthesis, cell division Nucleolus is a dark dot in the nucleus makes ribosomes and stores proteins and RNA

Nuclear Envelope or Nuclear Membrane Double membrane where substances enter and leave through pores (nuclear pores)

Cell Wall Located outside cell membrane, has pores Supports and protects plant Made of cellulose Nonliving Plants, fungus, bacteria

Vacuole Large fluid filled membranous sac Stores , enzymes, metabolic wastes Pressure of water keeps plants from wilting

Plastids Have 2 membranes Function- store energy in sugar molecule bonds Types…

Plastids (plants only) Chromoplast Pigments for red, orange, and yellow color fruit, flowers, leaves Chloroplasts Contain chlorophyll (green) trap sunlight for photosynthesis

Leucoplast Found in plants Colorless Starch storage

Ribosomes Make proteins and enzymes Found free floating in the cytoplasm and attached to the endoplasmic reticulum Has no membrane In Eukaryotic and Prokaryotic cells

Endoplasmic Reticulum FUNCTIONS Makes protein and enzymes makes steroids (gland cells) regulates calcium levels in muscle breaks down toxic substances in the liver Rough ER - has ribosomes Smooth ER - has NO ribosomes stores what the RER makes

Golgi Apparatus/Golgi Complex Add lipids or carbohydrates to proteins made by rough ER and ribosomes Golgi then package the finished proteins and transports them for export

Lysosomes Small sacs of powerful digestive enzymes which cleans up cellular wastes by dissolving them Made by golgi

Centrioles Rod shape structure Used during mitosis and is responsible for spindle formation and movement Animals only Made of microtubules

Cytoskeleton Called microtubules Hollow tubes that support cells and move cells Maintains shape and size of cell Microfilaments: protein fibers used to move organelles and used in muscle contractions

Cilia/Flagella Hair like organelle for movement Cilia-many and short Flagella-few and long -tail like Made of microtubules

Flagella and Cilia Movement

Mitochondria Provide energy for the cell by converting glucose and oxygen into A.T.P.(energy molecule) Called the powerhouse of the cell Cristae increases surface area for chemical reactions

Chromatin Fine strands Combination of DNA and protein Located in nucleus When tightly packed they are called chromosomes Stores heredity info

Differences Between Plants and Animals Animals have centrioles, many small vacuoles, Plants have cell walls, large central vacuole, and chloroplasts

Cell Action Harvard 3D animation