Cell structure & Function
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Transcript of Cell structure & Function
CELL STRUCTURE & FUNCTION
CELL WALL Main function –
provide support & protection for the cell
Made of cellulose (carbohydrates) and protiens
Located outside the cell membrane of plant, fungi, and some protist cells
CELL MEMBRANE Main function – outer boundary of cell;
regulates what can enter and exit the cell Composed of a phospholipid bilayer w/
proteins embedded in the membranes; carbohydrates may attach to proteins
CYTOPLASM Main function –
substance where organelles are suspended; site of many chemical reactions
Fluid substance that fills the space between the cell membrane and the nucleus
NUCLEUS Main function – controls
most cell processes and contains hereditary information (DNA)
Composed of a Nuclear membrane Nuclear pores Nucleolus Chromatin/Chromosomes
Located in all eukaryotic cells
Scanning ↑Transmission ↓
CHROMATIN/CHROMOSOMES Chromatin – DNA &
Protein when it is loose and thread-like; granular looking; most of the time
Chromosomes – DNA & Protein when it condenses to form distinct structures; when cells are dividing
NUCLEOLUS Main function –
production / assembly of ribosomes
Dense region within the nucleus
NUCLEAR MEMBRANE Main function –
surround and protect the contents of the nucleus
Double membrane layer
Dotted with thousands of nuclear pore which allow material to move into and out of the nucleus
CYTOSKELETON Main function – help the
cell maintain its shape; also involved in many forms of cell movement
Network of protein filaments Microfilaments –
smallest; movement & support
Intermediate filaments – medium sized
Microtubules – largest; transport; cilia; flagella
RIBOSOMES Main function – site
of protein synthesis Composed of RNA
and protein Can be free floating
in the cytoplasm or attached to endoplasmic reticulum
ENDOPLASMIC RETICULUM Rough ER Main
function – manufacture and distribution of proteins; ribosomes are attached
Smooth ER Main function – manufacture of lipids and break down toxins; NO ribosomes are attached
GOLGI APPARATUS Main Function –
modifies, packages, and distributes material in the cell; Material is received from the ER, modified in the Golgi, then sent to the cell or out of cell.
Stack of membranes
LYSOSOME Main function –
break down food and/or worn out organelles
Small sack containing digestive enzymes
VACUOLE Main function –
store materials such as water, salts, proteins, and carbohydrates
Plants have a large central vacuole that help the plant stand upright
Saclike structures
CHLOROPLASTS Main function – use
energy from sunlight to make energy-rich food molecules; site of photosynthesis
Double membrane structure that contain large states of green membranes; green color is due to the pigment chlorophyll
MITOCHONDRIA Main function – use
energy from food to make high-energy compounds that eh cell can use to power growth, development, and movement
Double membrane structure; inner membrane is highly folded
ENDOSYMBIOSIS
Theory that states - mitochondria and chloroplasts are descendents from ancient prokaryotic cells that were engulfed by other cells; the two cells formed a symbiotic relationship where both cells benefited. Evidence = mitochondria & chloroplasts have DNA, ribosomes, and can divide independently of the cell