The study of living things Life Science : Biology The study of living things

Structure and Function Different organisms may have different structures that do the same job. Example: cilia, flagella, wings, fins & legs help organisms move

Cells Basic unit of structure and function of life. New cells can come only from existing cells

Prokaryotic Cell Prokaryotic Cell Pro = “before”,karyon = “nucleus” Smaller Less complex and less organized Includes few cell structures Lacks nucleus - DNA floats freely Example Organisms: bacteria

Eukaryotic Cell Eukaryotic Cell Eu = “true”, karyon = “nucleus” Larger   Larger More complex and more organized Includes many cell structures Has nucleus - DNA enclosed inside Example organisms: plants and animals

Cell Membrane Encloses the cell allowing some materials to pass through it, but not others

Cytoplasm Mostly water, with other substances dissolved in it

Nucleus Home to the cell’s chromosomes which are genetic structures that contain the information used to direct cell activity and make new cells Made of DNA

Nuclear Membrane Surrounds and protects the nucleus

Nucleolus Responsible for making ribosomes

Vaculoes Fluid-filled structures temporarily store different substances needed by the cell Some storing waste products

Mitochondria Use oxygen to transform the energy in food

Endoplasmic retiulum (and ribosomes) Produce important products for the cell including proteins and lipids Internal delivery system for the cell

Golgi bodies Help package products form the endoplasmic reticulum and distribute them around the cell.

Choroplasts (plant cells only) Food-making structures of plant cells containing the green pigment, chlorophyll Sunlight, water and carbon dioxide to make glucose—the simple sugar plants us as food. Process is called photosynthesis

Prokaryotic Cell vs. Eukaryotic Cell Similarities   Both have cell membranes. The cell membrane controls the flow of materials in and out of the cell  Both have cytoplasm. Cytoplasm is the jellylike substance that fills the cell  Both have DNA  Both need energy

Unicellular Made of only one cell Single cell carries out all the activities of life that keep the organism alive and allow it to move, get food, reproduce and respond to its surroundings.

Multicellular Made of many cells Cells work together to carry out all the activities of life that keep the organism alive and allow it to move, get food, reproduce and respond to its surroundings. Cells are specialized

Robert Hooke First person to observe cells in the 1660’s.

Characteristics of a Eukaryotic Cell Large – about 10 times bigger than prokaryotic cells Complex and well-organized includes many cell structures, which perform a specific function within the cell Has nucleus – DNA enclosed inside Plants and animals are examples of multi-celled, eukaryotic organisms

Animal Cell

Plant Cell

Similarities of Plant and Animal Cells cell membrane: controls the flow of materials in and out of the cell vacuole: fluid-filled sac that stores different materials mitochondria: supply energy ribosome: makes proteins nucleus: contains DNA endoplasmic reticulum: moves materials to other cell structures cytoplasm: jellylike substance that fills the cell

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