Download notes p. 107-108 - Madeira City Schools

I. Introduction to the Cell “With the cell, biology discovered its atom.” –Jacob
A. The cell is the smallest unit that can carry on the 6
characteristics of life.
1. obtain/use energy
2. interacts with other organisms
3. reproduce
4. maintain balance with environment
5. grow/develop
6. structure
B. Discovery of the cell -- made possible by
invention of the microscope in
1600s.
1.  Leeuwenhoek (Dutch)- first
person to observe living cells
2. Robert Hooke (English)observed cork from the bark of an
oak tree, gave name “cells”
because they looked like the cells
or rooms in a monastery.
II. Formation of the Cell Theory
A. What is the cell theory?
1. all living things are composed of one or more cells
2. cells are the basic unit of life
3. cells only come from other cells
C. A series of experiments proved Spontaneous
Generation wrong.
http://www.sumanasinc.com/webcontent/animations/content/scientificmethod.html
B. What they used to believe: Spontaneous Generation (living
things come from nonliving things), examples:
1. mud produces fish
2. puddles of water produce microorganisms
3. rotting meat produces flies
4. stale bread produces mold
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Notes to add on Redi and Pasteur
•  Redi -- showed that sealed rotting meat
didnt produce maggots:
– meat with netting did have them, but on
the netting ONLY
– plenty of maggots on uncovered meat
because flies free to lay eggs on it
– conclusion: only flies can make flies,
rotting meat doesn’t turn into flies
III. Cell Diversity
A. Shape
1. different shapes because they have different functions
•  Pasteur -- sterile broth in 2 flasks
–  broth in flask with straight neck grew
microorganisms because dust (with
microorganisms) could get in
–  swan-necked flask had no microorganisms-air could get into flask but dust couldn’t
–  conclusion: only living cells can produce new
cells
B. Size:
There is a limit of size due to the speed at which materials need
to get into and out of the cell. The cell needs enough surface
area compared to its volume to be able to bring in necessary
substances and eliminate waste products.
a. nerve cells – long extensions to receive and give
messages
b. flat skin cells – to protect
c. white blood cells change shape so they can move
through narrow openings
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B. Cytoplasm (cytosol): “background” space within the cell,
everything that’s not an organelle
1. jelly-like material that contains water, salt, sugars, fats
and proteins – allows reactions to take place
2. always moving, so substances in cell are circulated
throughout
Contains DNA
Makes ribosomes
Protects the nucleus
Allows things to go in and out of the
nucleus
Not membrane
bound
Makes proteins
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Rough because it is covered in ribosomes
Makes, packages, and transports protein
Packages and transports protein and fat
Contains digestive enzymes
Where polysaccharides are made, packaged, and transported
Attaches carbohydrate tags to cell membrane proteins
Breaks down foreign material,
old cell parts, and food.
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Tubulin…the protein that
makes up a microtubule
Hollow tube that makes up
cytoskeleton.
Where food (glucose, fatty acids) is used
to make energy (ATP)
Gives cell its shape, helps in
movement and helps in cell division
Solid protein
thread that
makes up
cytoskeleton
Adipose Tissue (fat cells store fat
in a large central vacuole)
Organelle that stores food, waste,
and/or water.
Plants have 1 large one and
animals have many small ones.
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Tiny hairs on the
cell surface
Moves the cell OR
Tail-like structure
Moves things
around the cell
Moves the cell
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