CELLS CELLULAR COMPONENTS & PROCESES CELL THEORY 1. All living things are made up of one or more cells 2. The cell is the smallest unit of life. 3. All new cells come from pre-existing cells. There are two types of cells: 1. Prokaryotic- cells that DO NOT have a nucleus or other membrane bound cell ORGANELLES 2. Eukaryotic- cells with a NUCLEUS & membrane bound cell ORGANELLES Which is more complicated? REMEMBER YOU ARE EUKARYOTIC! 1
Label the parts of the animal cell. A. Cytoplasm B. Cell membrane C. Golgi Body D. Lysosome E. Endoplasmic Reticulum F. Nucleus G. Mitochondria H. Ribosome Image: http://web.jjay.cuny.edu/~acarpi/nsc/13-cells.htm 1 2 3 4 5 6 7 8 B. Cell membrane E. Endoplasmic Reticulum F. Nucleus H. Ribosome D. Lysosome G. Mitochondria C. Golgi Body A. Cytoplasm The answers are 2
Label the parts of the plant cell. Cytoplasm Cell Wall Vacuole Endoplasmic Reticulum (ER) Nucleus Mitochondria Cell Membrane Chloroplast Image: http://fds.oup.com/www.oup.co.uk/images/oxed/children/yoes/nature/plantcell.jpg The answers are Cytoplasm Vacuole Chloroplast Mitochondria Nucleus Cell Wall Cell Membrane Endoplasmic Reticulum (ER) Organelles The parts of a cell that carry out a function are called cell ORGANELLES: All cells have the following organelles: Cell Membrane Cytoplasm Ribosomes Cytoskeleton 3
Cell Appendages Cilia Short, numerous hairlike structures Flagella Longer and less numerous than cilia Create movement with a whiplike motion Eukaryote cells ALSO have: Nucleus Nucleolus Mitochondria Golgi Body Complex Endoplasmic Reticulum Vacuole Lysosome Centrioles (ANIMAL ONLY) Only Plant Cells have all of the above &: Cell Wall Chloroplast organelles little organs of the cell Organelles are present in BOTH plants and animals Carry out cellular functions! 4
Nucleus Nucleus is the part of the eukaryotic cell that directs cell activities and contains genetic information stored in DNA. DNA is organized into structures called chromosomes. Nuclear membrane surrounds nucleus allowing certain materials to enter and leave 5
Nucleolus Is often seen as a large dark spot in the nucleus of the cell. usually a pair The nucleolus makes ribosomes, organelles that are involved in the production of proteins. Ribosomes Ribosomes are not surrounded by a cell membrane. Ribosomes are in the cell s cytoplasm and can also be attached to a web-like organelle called endoplasmic reticulum. Ribosomes produce proteins. 6
Endoplasmic reticulum (ER) ER spreads from the nucleus throughout most of the cytoplasm. ER with ribosomes on its surface is called rough endoplasmic reticulum. ER without ribosomes on the surfaces are called smooth endoplasmic reticulum. Endoplasmic reticulum (ER) Rough ER is the site for protein synthesis. Smooth ER makes lipids such as cholesterol. Smooth ER is important because it removes harmful substances from the cell. 7
Cytoplasm (protoplasm) fluid like material between the cell membrane and the nucleus over 80 % water HOLDS cell organelles in place site of most organelles and cellular chemical reactions Vacuole Vacuoles are organelles that store food, water and waste material. Vacuoles are crucial in single-celled organisms Two Types: Food vacuole--store and digest ingested food Contractile vacuole-pumps excess water from cells maintaining homeostasis. 8
Lysosome pouch containing digestive enzymes digest bacteria and some foods entering the cell Breaks down complex molecules into simpler molecules (SLICE) breakdown worn out cell organelles 9
Mitochondrion "Powerhouse of the cell" carries on cellular respiration. Energy is released (contains respiratory enzymes that make ATP) (energy molecule) The energy is stored in high energy molecules called ATP ( Adenosine triphosphate Golgi apparatus (complex) usually located near the nucleus synthesizes, packages, and secretes cellular products Packages waste & harmful materials Plasma (cell) membrane The cell membrane is SEMI-PERMEABLE selectively regulates the flow of materials to and from the cell--thus maintaining chemical homeostasis within the cell The membrane acts like a BOUNCER only allowing certain things in and out of the cell It is made up of a lipid bilayer double layer of FAT - "Fat sandwich" transport through the plasma membrane likely occurs through these globular proteins (Fluid mosaic model) 10
Hydrophilic- attracts water Hydrophobic- repels water Why is it important that the cell membrane is made up of small phospholipids? ANIMAL CELL ORGANELLES ONLY Centriole- a cylindrical structure found in the cytoplasm which appears to function during the division of certain animal cells (usually near the nucleus) Helps animal cells divide 11
PLANT CELL ORGANELLES ONLY Cell Wall- a nonliving structure which surrounds and supports the cell - composed mostly of cellulose Gives the plant cell structure & support Chloroplasts- green in color-double membrane - contain the green pigment chlorophyll which carries on photosynthesis Uses the sun s energy to make food for the plant photosynthesis the conversion of light energy to chemical energy by chlorophyll in chloroplasts Overall Net equation for photosynthesis: 6 Water + 6 Carbon dioxide yields glucose + 6 oxygen (when catalyzed by chlorophyll in the presence of sunlight) 12
Levels of Tissue Organization cell - unit of structure of all life tissue - composed of groups of similar cells organs - composed of groups of tissues functioning together organ systems - composed of groups of organs functioning together 13