Biology Chapter 4 CELLS
Introduction to cell Cell Theory 1. All living things are made of cells 2. Cells are the basic unit of structure & function 3. Cells only come from other living cells
Cell Scientists 1. Hooke first to call them cells 2. Leeuwenhoek first to see living cells 3. Schleiden 1st to say all plants have cells 4. Schwann 1st all animals have cells 5. Virchow all cells come from other cells
CELL SIZE limited to the ratio between outer surface area and the volume larger the ratio the better if a cell gets too big it cannot get nutrients in or wastes out fast enough microwave baked potato
Cell Diversity Cell Shape shape is determined by its function Organization all have membranes All have genetic information
Cell Types 1. Prokaryotes no nucleus no membrane bound organelles EX: bacteria
Cell Types 2. Eukaryotic--True nucleus Have membrane bound organelles small structures that have specific function in the cell EX: plants, animals
Eukaryotic Cells 3 Major Regions 1. Cell Membrane 2. Cytosol with cytoplasm 3. Nucleus
Parts of a Eukaryotic cell Cell Membrane Selectively permeable Some things pass through others do not Phospholipid bi-layer 1. Water loving (hydrophilic) heads 2. Water fearing (hydrophobic) tails Proteins- on the surface & within the bi- layer
Parts of a Eukaryotic cell Mitochondria make ATP / energy have folded membrane called cristae Ribosome make proteins Golgi Apparatus → package proteins
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Parts of a Eukaryotic cell Endoplasmic Reticulum transports proteins smooth = no ribosomes rough = have ribosomes Lysosome break down old cell parts only in animal cells Cytoskeleton microfilaments & microtubules
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Parts of a Eukaryotic cell Cillia short & many hair like move substances or cell Flagella long & one hair like, move cell
Parts of a Eukaryotic cell Nucleus Has nuclear envelope chromatin that becomes chromosomes nucleolus – makes ribosomes pores – allow things in & out of nucleus control center of cell
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Parts of a Eukaryotic cell Cell wall* made of cellulose support for a plant cell Vacuoles* store wastes & enzymes can be very large Plastids* have pigments that absorb light chloroplasts – chlorophyll- photosynthesis chromoplast – different color amyloplast – store starch
Plant or Animal
Multicellular Organization Cells working together make up tissue Tissues working together make organs Organs working together make organ sys Organ Systems make up organism
Colonial organisms are thought to be a link between uincellular & multicellular organisms Each cell is responsible for their own self, some do functions that benefit the whole group. EX: Volvox.