The Cell Cell Types & Cell Parts. Cell Types Prokaryotic Cells or Prokaryotes The Bacteria.
The cell
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1 Organisms and Cells d. c. b. a. 50 m 140 m Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a: © Geoff Bryant/Photo Researchers, Inc.; b: Courtesy Ray F. Evert/University of Wisconsin Madison; c: © Barbara J. Miller/Biological Photo Service; d: Courtesy O. Sabatakou and E. Xylouri-Frangiadak
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Transcript of The cell
1Organisms and Cells
d.
c.
b.
a.
50 m 140 m
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
a: © Geoff Bryant/Photo Researchers, Inc.; b: Courtesy Ray F. Evert/University of Wisconsin Madison;c: © Barbara J. Miller/Biological Photo Service; d: Courtesy O. Sabatakou and E. Xylouri-Frangiadak
Multicellular organisms are arranged from simple to complex according to their level of cellular grouping.
cell tissue
organ organ system
organism
The Levels of Organization
Cells
Smallest living unit Most are microscopic
Cells have 3 main jobs make energy
need energy for all activities
need to clean up waste produced while making energy
make proteins proteins do all the work in a cell,
so we need lots of them
make more cells for growth
to replace damaged or diseased cells
The Jobs of Cells
Our organellesdo all thesejobs!
ATP
Principles of Cell Theory All living things are made of cells
Smallest living unit of structure and function of all organisms is the cell
All cells arise from preexisting cells(this principle discarded the idea of spontaneous generation)
Why study cells? Cells Tissues Organs Bodies
bodies are made up of cells cells do all the work of life!
Cells have 3 main jobs make energy
need energy for all activities need to clean up waste produced
while making energy make proteins
proteins do all the work in a cell, so we need lots of them
make more cells for growth to replace damaged or diseased cells
The Jobs of Cells
Our organellesdo all thesejobs!
ATP
Cell Size
Cell Types
Prokaryotic
Eukaryotic
Cell Type: Prokaryotes Prokaryotes, which includes all bacteria, are the simplest cellular
organisms. They have genetic material but no nucleus.
Typical bacteria cellBacteria cells
Cell Types: Eukaryotes Eukaryotic cells contain a
membrane-bound nucleus and numerous membrane -enclosed organelles
Cell size comparison
Bacterial cell
Animal cell
micron = micrometer = 1/1,000,000 meter diameter of human hair = ~20 microns
most bacteria 1-10 microns
eukaryotic cells 10-100 microns
Organelles Organelles do the work inside cells
each structure has a job to do keeps the cell alive; keeps you alive
Model Animal Cell
They’re likemini-organs!
cytoplasmjelly-like material holding organelles in place
20Photograph of a Cell Membrane
KEY CONCEPT The cell membrane is a barrier that separates a cell from the external environment.
Function separates cell from outside controls what enters or leaves cell
O2, CO2, food, H2O, nutrients, waste recognizes signals from other cells
allows communication between cells Structure
double layer of fat phospholipid bilayer
receptor molecules proteins that
receive signals
Cell membrane
lipid “tail”
phosphate“head”
3.3 Cell Membrane
Cell membranes are composed of two phospholipid layers.• The cell membrane is selectively permeable.
Some molecules can cross the membrane while others cannot.
copyright cmassengale
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Cell Membrane
Polar heads are hydrophilic “water loving”
Nonpolar tails are hydrophobic “water fearing”
Makes membrane “Selective” in what crosses
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Cell Membrane
Hydrophobic molecules pass easily; hydrophilic DO NOT
What is the function of the protein channels?
They provide passageways for materials to cross the membrane.
Nucleus Control center of cell
Double membrane
Contains Chromosomes -DNA Nucleolus The nucleus is a home to the cell’s
chromosomes and DNA. What are chromosomes you ask?Chromosomes: They are genetic structures that contain information to make new cells. Basically, the instructions for how to make new cells.
Terms/Structures continued Nucleus: The nucleus is a structure usually located near the
center of the cell. The nucleus is a home to the cell’s chromosomes and
DNA. What are chromosomes you ask? Chromosomes: They contain information to make new cells.
Basically, the instructions for how to make new cells.
Terms/Structures continued Nucleolus: This structure is found inside the nucleus. It
is responsible for making ribosomes. We will get to this term in a bit. Thanks for your patience!
Make proteins for cell repair and reproduction
Mitochondria
Golgi bodiesOr
Golgi Apparatus
