Cells pgs 59-63 odd

What is a Cell? Cells are the basic structural and functional units of all organisms Multicellular- simple to complex (fungi) animals and plants Unicellular Single-Celled Bacteria and some yeasts, fungi and algae

History First to observe living cells 1595 1665 Hans and Zacharias Janssen Dutch lens grinders, father and son Produced first compound microscope 1665 Robert Hooke English Scientist studied the cork tree and called the holes in the cork “cells” Things are made of cells History 1680’s Anton van Leeuwenhoek Dutch fabric merchant and amateur scientist looked at blood, rainwater, scrapings from teeth through a simple microscope First to observe living cells 1838 Matthias Schleiden German botanist Used a microscope to study plants Determined plants are made of cells 1855 Rudolph Virchow German doctor who discovered that new cells do not form on their own.  New cells form when old cells divide 1839 Theodor Schwann German Studied animals All animals are made up of cells

The Cell Theory This all leads to…. Cells are the basic units of structure and function in living things All living things are composed of one or more cells New cells are produced from existing cells

Two Types of Cells Prokaryotes First cells on Earth Single celled organisms Lack a nucleus Lack membrane bound organelles Small (ex: bacteria) Grow in all environments Genetic Material is a single circular molecule of DNA Cell Wall (structure and support)

Eukaryotes Nucleus Organelles (structures that carry out specific activities of the cell) More complex than Prokaryotes Plants, Animals, some fungi, algae, and yeasts)

Why do cells need all these things? …because they keep cells alive Cell Wall Basic Cellular Functions Molecule Transport Must be able to obtain nutrients and other molecules to survive Reproduction produce new generations to ensure the survival of their species Energy Conversion Convert energy into something the cell can use (Ex: Glucose to ATP) Chloroplasts Cytoskeleton Cell Membrane Endoplasmic Reticulum Vacuoles Chromosomes Membrane Proteins Ribosomes Golgi Apparatus Nucleus Cytoplasm

What Makes the Cell Run? ….hint (it’s a macromolecule) Proteins Necessary for reading cell’s DNA Generation of ATP (energy cell’s can use) Cell communication Interaction with their environment e.g. adhesion of objects to cells) Structure (cytoskeleton) Breakdown of cellular waste ...the list can go on and on. If the cells cease to make proteins, they will cease to function and, ultimately, cease to exist.

Why are Cells so small Small cells exchange substances easier because they have a low volume to surface area ratio. Substances don’t need to travel as far to reach center.