cell structure & function famigletti teks 7.12 d) differentiate between structure and function...
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Cell Structure & Function
Famigletti
TEKS 7.12D) Differentiate between structure and function in plant an animal cell organelles including cell membrane, cell wall, nucleus, cytoplasm, mitochondrion, chloroplast & vacuole
E) Compare the functions of a cell to the functions of organisms such as waste removal
F) Recognize that according to cell theory all organism are composed of cells and cell carry on similar functions such as extracting energy from food to sustain life
• The Cell Theory grew out of the work of many scientists and improvements in the microscope.
Scientists that contributed to the Cell Theory: Hooke: Leeuwenhoek: Schleiden: Schwann: Virchow:
• Early studies led to the development of the cell theory.
The Cell theory has three principles.1. All organisms are made up of cells2. All existing cells are produced by other living cells3. The cell is the most basic unit of lif e
Two Types of Cells
•Prokaryotic•Eukaryotic
Cells are the basic unit of lifeall living things share the following
characteristics:
• Growth• Response to environment• Reproduce• Get & use energy• Get rid of waste• Adapt to changes
There are two cell types: Prokaryotic cells and Eukaryotic cells.
All cells share certain characteristics.
1. All cells are enclosed by a membrane
2. All cells are fi lled with cytoplasm; a jellylike substance that holds things
Bacterium(colored SEM; magnification 8800x)
cell membrane
cytoplasm
Prokaryotic
Pro- NO
• NO nucleus
• NO-membrane bound organelles
• Few internal structures
• One-celled organisms, Bacteria
http://library.thinkquest.org/C004535/prokaryotic_cells.html
Eukaryotic
Eu- YOU• Contain organelles surrounded by membranes,
including nucleus! • Most living organisms including plants & animals
Plant Animal
http://library.thinkquest.org/C004535/eukaryotic_cells.html
“Typical” Animal Cell
http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif
http://waynesword.palomar.edu/images/plant3.gif
“Typical” Plant Cell
Examples of CellsAmoeba Proteus
Plant Stem
Red Blood Cell
Nerve Cell
Bacteria
Which is the prokaryote?
Bacteria!
Internal Structures& their functions
Cell Membrane
• Outer membrane of cell that controls movement in and out of the cell
• Cell membrane protects and separates the rest of the cell from external environment.
• Double layer that only allows specific things through
http://library.thinkquest.org/12413/structures.html
The cell membrane is a barrier that separates a cell from the external environment.
Cytoplasm• Jelly-like substance
• Is everywhere inside the cell membrane and outside the nuclear membrane
• Cytoplasm important for cell structure
• Water allows chemical reactions to occur
• Provides medium for chemical reactions and movement between organelles
• Cytoskeletonhas many f unctions1. Microtubules give
cells shape; move DNA
2. I ntermediate fi laments, give cells strength
3. Microfi laments allow cells to move and divide
Cytoskeleton
Centrosome and Centrioles
• Specialized parts of the cytoskeleton
• Centrioles are tubes found in the centrosomes
• Centrioles help divide DNA during mitosis.
• Centrosomes make microtubles which make spindle fibers
NucleusStores genetic information
• Nuclear envelope – double membrane that encloses DNA
• Nuclear Pores –
• Nucleolus – contains tiny organelles f or making proteins
Endoplasmic Reticulum
Series of folded membranes“I ntracellular Highway”
Many processes occur on surface and lumen (interior of membranes)
ex: Production of proteins and lipids
Endoplasmic Reticulum• There are two types:
– Rough Endoplasmic Reticulum (R.E.R.): contain ribosomes
– Smooth Endoplasmic Reticulum (S.E.R.): no ribosomes
Lumen
Ribosome's link amino acids to f orm proteins
Made of protein and RNA
Made in nucleolus; leave through nuclear pores
Ribosome
Golgi Apparatus
• Closely stacked membranes• Package, Sort, and Processes
Proteins f rom the E.R.
Mitochondria• Supply energy to the cell
• Consists of two membranes; inner membrane has lots of folds, Why?
• Have their own DNA and ribosomes
• Fluid-fi lled sacs used f or storage• Central vacuole unique to plant cells
– plants shrivel when central vacuoles don’t have enough water
– Can contain toxins that help the plant survive
Vacuoles
• Contain enzymes inside to digest material; defend cell f rom invading bacteria and viruses
• Surrounded by a membrane; protects cell f rom being broken down
Lysosomes
Plant cellsHave TWO features Animal Cells Do Not
Cell wall: gives protection, support, and shape to cell
Chloroplasts: organelles that perform photosynthesis
Cell Structure & function• Animal cells have various structures so that
they may perform their individual functions to the best of their ability
Neuron• The unique structure of the neuron is
dedicated to the efficient and rapid transmission of neural signals.
Red blood cells• Red blood cells lack a nucleus which
helps them to squeeze through tight capillary spaces
Cell Movement• Some cells have structures to hel them
to move.• These structures are cytoskeleton
extensions, called cilia or flagella.