UNIT 3 Systems (1.1) Cell Parts (p3-15)
WHAT YOU WILL LEARN: Special structures of cells which perform important life functions. Technologies used to study cells. Similarities and differences between plant and animal cells.
Why Study Cells? Studying cells helps us understand how organisms, like humans, function. Think about it.... Do you think the cells in the grass are the same as the cells in the elephants? Are all grass cells the same?
Copyright © 2010 McGraw-Hill Ryerson Ltd. Big Ideas The following terms describe different levels of organization in many-celled living things. Place the four terms in order, from the smallest level of organization to the largest level of organization. organs tissues cells systems
Robert Hooke Credited with the discovery of the cell Looked at cork cells (plant) Thought that the “empty” spaces were for fluid passage in plants He had no idea how important this discovery was to be.
Technology of cell study Earlier scientists used simple light microscopes to observe cells. While these microscopes did help learn about the external structures of the cell they revealed few details about the structures inside cells. Today electron microscopes allow scientists to see deep into a cell.
The Cell Theory 1: All living organisms are made up of cells. 2: The cell is the basic structural unit of living organisms. 3: The cell is the basic functional unit of living organisms. 4: All cells come from pre-existing cells.
Organelle An organelle - is a structure within a cell - carries out special functions to support the life of the cell including: intake of nutrients waste removal release and generation of energy for the cell reproduction production of material that the cell needs
Cell Parts & Function Each organelle has a specific role within a cell. Some cells have more of one type of organelle and fewer of others. Cells exist in great variety. - Animal cells are different than plant cells. - In animals cells nerve cells, heart cells, skin cells, bone cells are all different. However, cells consist of basically the same structures or parts.
Copyright © 2010 McGraw-Hill Ryerson Ltd. Animal Cell Organelles (p14)
Copyright © 2010 McGraw-Hill Ryerson Ltd. Plant Cell Organelles (p15)
Cell Membrane Every cell has a cell membrane Forms a protective barrier around the cell Designed to allow different substances to move in and or out of the cell.
Cytoplasm Organic fluid in all cells Composition varies Contains material needed by cell to perform cell functions
Mitochondria (singular-mitochondrion) Tiny, sausage-shaped structures Release energy for cell functions Called the "powerhouse“ of cell
Ribosomes Small, dense-looking organelles that may be attached to rough endoplasmic reticulum or free floating in the cytoplasm. The site where proteins are assembled.
Endoplasmic Reticulum Small interconnected tubes that carry material around the cell. Two Types: Rough ER and Smooth ER Rough ER has ribosomes attached.
Vacuoles and Vesicles -clear, fluid-filled sacs -used for storage of water, food, minerals, and waste Vacuoles - larger and less numerous in plant cells - smaller in animal cells Vesicles - transport substances throughout the cell
Plant & Animal Vacuoles
Golgi Body (Also called Golgi Apparatus) Take proteins from the endoplasmic reticulum and modify, sort, and package them for delivery throughout the cell.
Nucleus A large organelle usually found near the center of the cell Control center of the cell, directs all cell activity Involved in cell division, contains chromosomes containing DNA organized into units called genes
Cytoskeleton Filaments and tubules within cell Provide framework for cell Helps cell keep its structure Aids movement of materials in and out of cell
Cell Wall Only in plant cells Tough rigid structure outside of cell membrane Provides support for cell
Chloroplasts Found only in plant cells Contain a green pigment called chlorophyll used in photosynthesis Through photosynthesis energy from the Sun is trapped and glucose is formed
Plant & Animal Cell Comparison Plant CellsAnimal Cells Chloroplasts Large central vacuole Fixed shape (rectangular) No chloroplasts Small, numerous vacuoles Irregular shape
Tools for Cell Research Cells are VERY small. Today biologists use different microscopes to explore cell structure and function. compound light microscope electron microscope
Animal Cells - Examples blood cellsnerve cells cheek cells
Plant Cells-Examples onion cellselodea plant cells
HOMEWORK Textbook: p 13 LC #1-4 p 15 LC #1-3