Transcript Cells Notes

Cells
Chapter 2
Page 48
• Cell theory: Robert Hooke first looked at
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and described cells in 1665. The word
“cell” means “little room” in Latin.
Anton Leeuwenhoek first described
protists, blood cells, and bacteria in the
later 1600s.
We now know all living things are made of
cells. Cell theory, written in the 1800s,
says three things: 1. All organisms are
made of one or more cells.
The cell is the basic unit of life.
All cells come from existing cells.
PARTS OF A CELL:
Cell membrane-protective layer; acts as
barrier; controls what goes in and out
Cytoplasm-the fluid and it’s dissolved
contents inside the cell
Organelles: carry out various processes within the cell;
most have their own membranes; some float in cytoplasm
Nucleus: Only present in Eukaryotic (cells with
nuclei) cells; contains the DNA in eukaryotic
organisms (not bacteria)
Eukaryotic Cells p. 56
• Include plants and
animals
• All have a nucleus-large
organelle w/ DNA; DNA
directs the production of
proteins; covered by two
membranes; contains
the nucleolus (where
ribosomes are made)
Plant Cells
• The main differences in plant and animal cells
is that plant cells have a cell wall (provides
support) and chloroplasts (where
photosynthesis takes place).
• Plants’ cell walls are made of cellulose, a
complex sugar. This is why celery crunches
when you bite it.
• Chloroplasts have their own membranes and
DNA. They contain chlorophyll, which makes
them green. This is also what traps the energy
of sunlight.
All Eukaryotic Cells have
• these…
Cell membrane-contains proteins, lipids,
and phospholipids; lipids are fat and do not
dissolve in water; protein passageways
allow movement of materials in and out.
• Cytoskeleton-keeps the cell’s membranes
from collapsing and allows some to move
• Ribosomes-make proteins; smallest
organelles; more than any other organelle
in a cell; some are attached to the rough
ER (prokaryotes have ribosomes too!)
•Endoplasmic Reticulum (ER): system of
folded membranes in which proteins,
lipids and other materials are made
through chemical reactions. Rough ER
makes proteins; smooth ER makes lipids
and breaks down toxins.
• Mitochondria: “powerhouse” of the cell;
sugar is broken down here to make
energy (ATP) through cellular respiration;
energy is found in ATP (adenosine
triphosphate)
Golgi Complex (apparatus)
• Packages and distributes proteins; looks
like smooth ER but is farther from the
nucleus; gets lipids and proteins from the
ER; modifies them to do different jobs
then sends them out of the cell
VESICLE
• Small sac that surrounds material to be
moved in or out of a cell.
REVIEW-write Q and A in
Assignments Section
1. Explain how the mitochondria and
chloroplast are related in a plant cell:
2. Make a chart showing how a plant and
animal cell differ.
3. How do the Golgi complex and
endoplasmic reticulum work together?
4. How does smooth ER differ from rough
ER?
Review-put in Assignments-write
Q and A
1. Why do you think plants need a cell wall?
2. What is the function of the mitochondria?
3. Ribosomes make ____________but
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ribosomes are made in the __________
The rough ER is covered in ________.
The smooth ER makes __________.
How are mitochondria and chloroplasts
alike?
(sect 3) What are the three advantages to
being multicellular?
REVIEW-ASSIGNMENTS-WRITE OUT
1. Compare and Contrast mitochondria and
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chloroplasts.
Explain the relationship between the Golgi
Complex and the ER.
What does the vacuole do?
What does the lysosome do?
What is the “powerhouse” of the cell?
What is the difference in the rough ER and the
smooth ER? (p. 59)
What are the two main differences in a plant and
animal cell?
What is a lipid and how is it used in your cells?