The Cell Theory Eukaryotic Cells Prokaryotic Cells Vacuole membrane in plant cells Regulates...
Transcript of The Cell Theory Eukaryotic Cells Prokaryotic Cells Vacuole membrane in plant cells Regulates...
Bridget Kelly
2
The Cell Theory
All organisms are composed of cells and the products of cells
All cells come from pre-existing cells
The cell is the smallest organisational unit of living things
Eukaryotic Cells Prokaryotic Cells
Organelle Functions
Organelle Description Function
Centrioles Pair of small cylindrical structures of microtubules.
Separation of chromosomes during cell division (animals and protists).
Chloroplast Green organelle made of many folded loops of thylakoid membrane.
Site of photosynthesis
Cytoplasm The contents of a cell other than the nucleus
Site of many chemical processes and reactions
Cytosol Fluid component of cytoplasm Location of organelles and site of anaerobic cellular respiration/glycolysis.
Cytoskeleton Network of microtubules and microfilaments
Provides support and framework for cells
Endoplasmic Reticulum
Network of intracellular membranes linked with plasma membrane and other membrane bound organelles
Rough – protein synthesis and processing, storage transport of materials
Smooth – processing, storage and transport of materials
Lysosomes Membrane bound vesicles Contain powerful enzymes that break down debris and foreign materials.
Mitochondria Composed of many folded layers of membrane
Site of aerobic respiration
Smaller and more primitive
Circular, free floating DNA
No Membrane bound organelles
Bacteria (Monera)
Larger and more complex
Linear, contained DNA
Membrane bound organelles
Animals, plants, protists, fungi
Bridget Kelly
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Nucleus Large, surrounded by double layers of membrane containing pores to allow movement between nucleus an cytoplasm
Contains genetic material and controls cellular activities.
Plasma Membrane
Phospholipid ‘fluid mosaic’ bilayer with embedded cholesterol, protein and other molecules.
Controls movement of substances into and out of the cell and is responsible for recognition and chemical communication.
Plastid Group of organelles found only in plant cells Contain pigments or food
Ribosomes Tiny organelles located in the cytosol Site of protein synthesis
Tonoplast Vacuole membrane in plant cells Regulates movement of substances into and out of plant cells
Vacuole Membrane bound liquid filled sacs Provide physical support and may be involved in intracellular digestion and water balance
Vesicle Membrane bound organelles Transport within cells
The Cell Wall:
Non-living structure outside the plasma membrane
Plants = cellulose
Bacteria = Chitin
Plants vs Animal Cells:
The Plasma Membrane:
Cholesterol: A packing molecule that interacts with the phospholipids to regulate membrane consistency
Phospholipid Bilayer: Forms selectively permeable membrane that lets small molecules squeeze between and
lipid soluble molecules diffuse through hydrophobic tails.
Feature Animal Cell Plant Cell
Cell Wall Absent Present
Shape Irregular Rectangular (fixed)
Vacuole One or more (small) One (large)
Centrioles Present in all In lower forms
Chloroplasts Absent Present
Plastids Absent Present
Lysosomes Present Absent
Cilia Present Very rare