CELLS Prokaryotic and Eukaryotic Cells and Organelles

What is the Cell Theory? All living things are made of cells Cells are the (1) basic unit of structure and (2) carry out specific functions Cells come from other living cells

Scientists who contributed to the Cell Theory: Anton von Leeuwenhoek – invented the microscope. Observed tiny organisms in H 2 0 Robert Hooke – observed the cork had tiny chambers. Coined the term “Cell” Louis Pasteur - discovered cells only come from other living cells Francesco Redi - proved that living cannot be produced by a nonliving thing.

Two Types of Cells ProkaryotesEukaryotes

Comparison: ProkaryotesEukaryotes First cells to evolveEvolved from prokaryotes No nucleusHas a nucleus Ex: Archaea and BacteriaEx: Animals, Plants, Fungi and Protists Hereditary information is contained within the cytoplasm, not the nucleus Hereditary information is contained within the nucleus

Cell Organelles Tiny membrane bound structures that perform specific functions within the cell. Ex: cell wall, cell membrane, cytoplasm, mitochondria, chloroplast, lysosomes, golgi apparatus, ribosomes, vacuoles, endoplasmic reticulum, nucleus

Cell Membrane The surrounding for all cells In a plant cell, it is located beneath the cell wall In an animal cell, it is the boundary between the organelles and the outside world Made of cholesterol Provides support and protection Controls material movement in and out of the cell Cell Membrane

CELL WALL Outer covering of a plant cell, bacteria cell or fungal cell Rigid, strong, tough Made of cellulose Supports and protects the cell Cell Wall

Nucleus Found in both animal and plant cells Oval shape, large Located in the central part of the cell Controls the activities of the cell Contains DNA (hereditary material) for the cell Not developed in Eukaryotes Nucleus

Vacuoles Animal cells – contain many small vacuoles Plant cells – contain only a few large vacuoles Function to store food, water and waste products Fluid-filled sacs Vacuoles

Cytoplasm Clear, jelly like, thick material Located in plants and animal cells beneath the membrane Protects and supports the organelles within the cell cytoplasm Located in prokaryotic cells Cytoplasm

Mitochondria Similar to a kidney bean or jelly bean Located in animal and plant cells Functions to break down sugar molecules and release energy that is usable for the cell Inner folds (cristae) that increase the surface area internally Mitochondria

Ribosomes Located in both plants and animal cells Free floating in cytoplasm Can be attached to the Endoplasmic Reticulum Small organelles within the cell Produce proteins Free floating Ribosomes Attached Ribosomes

Golgi Apparatus In 1898, Camillo Golgi discovered… In plants and animal cells Flattened stack of bound membranes Golgi Body or Apparatus process and packages the molecules such as proteins and lipids that the cell produces. Golgi Apparatus

Endoplasmic Reticulum Located in both animal and plant cells A network of tubes that transports material throughout the cell Two specific types: Smooth (no ribosomes are attached) Rough (covered with ribosomes) Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum

Lysosomes Only located in animal cells Function to break down large molecules of food Functions also to digest old cell parts Shape is small and round Lysosome

Chloroplasts Located in plant cells Shape – Oval Function – use energy from the Sun in order to make food for the plant Color – green due to Chlorophyl Chloroplast

Additional Parts Of Cells Nucleolus – produces ribosomes and Holds DNA material Nuclear Membrane – outer covering of the nucleus, controls what passes in and out of the nucleus Vesicle – stores and transports substances from Golgi Body to the cell membrane for export Cytoskeleton – gives support and shape to the cell, made of proteins Centriole – (animal cells only) Organizes special parts of the cytoskeleton called microtubules for cell division, migrates to opposite ends (poles) of the cell to assist with cell division Centrosome – area of cell where microtubules are produced. Plant and animal centrosomes play similar roles in cell division Chromosome – contains most of DNA for living organism. Wrapped around protein complexes called nucleosomes and histones