1. Cell Theory
2. Anton van Leeuwenhoek- developed first
microscope.
a. Dutch biologist
5. Robert Hooke- English scientist looked at slices of
cork.
a. named them cells because they reminded him of
small monastery rooms called “cellulae,”
9. Robert Brown- 1833 Scottish scientist
a. observed dark structure near center- nucleus

2. 4. Matthias Schleiden- German botanist
stated all plants are made of cells, 1838.
4. Theodor Schwann- 1839 discovered all animals
are made of cells
7. Rudolf Virchow- 1855 German physician stated
all cells arise from the division of preexisting cells.

3. 1. All living things are composed of cells
2. Cells are the basic units of structure and function
3. All cells come from preexisting cells.

4. 1. Most cells are 5-50 micrometers in diameter.
a. Micrometer = one millionth of a meter.
3. Eukaryotic cells- contain a true nucleus and
membrane-bound organelles.
a. Examples: plants, animals, fungi, protists

5. 1. Prokaryotic cells- have no true nucleus or
membrane-bound organelles
a. Smaller than eukaryotic cells.
b. Examples: bacteria and cyanobacteria
5. Eukaryotic cells have 3 basic structures.
a. cell membrane, nucleus, cytoplasm.

8. 1. Regulates what enters and leaves the cell.
2. Aids in protection and support of the cell.
3. Composed of 2 layers of lipids called- lipid bilayer.
4. Peripheral proteins- stick to the surface of the lipid
bilayer.

9. 5. Integral proteins- free-moving and run through the
lipid bilayer.
a. some form channels that allow certain
molecules to pass.
b. some act as small pumps that push
molecules from one side of the membrane to
the other.
8. Carbohydrates attach to the proteins and act like
chemical identification cards, allowing cells to
recognize and interact with each other.

11. 1. Found in plants, algae, bacteria, fungi,
2. Lies outside the cell membrane.
3. Helps to protect and support the cell.
4. Very porous, water, oxygen, CO2, and other
substances can pass through easily.
6. Plant cell wall is made up of 2 or more layers.
a. 1st layer is made of pectin, holds cells together.
b. 2nd layer is called the primary cell wall, made of
cellulose.
c. Plants with woody stems form 3rd layer called the
secondary cell wall, made of cellulose and lignin.

13. 1. Controls all cellular activity.
2. Nuclear Envelope- 2 membranes form the boundary
around the nucleus
a. contain small openings called- nuclear pores.
3. Nucleolus- small region of RNA and proteins inside the
nucleus.
a. where ribosomes are made.
4. Chromosomes- structures made of DNA and proteins
that contain the genetic information of the cell.

15. 1. Cytoplasm- area between the nucleus and the cell
membrane.
a. contain organelles.
4. Mitochondria- change chemical energy stored in food
into compounds that the cell can use.
a. double layer outer membrane
b. Cristae- inner membrane and sight of the electron
transport chain where most ATP is made.
c. Matrix- space inside the inner membrane where
Kreb’s cycle takes place.
d. contains it’s own DNA.

17. 1. Found only in plants and algae.
• Surrounded by a pair of membranes.
3. Thylakoids- system of membranes arranged as
flattened sacs
a. Form stacks called grana.
b. Light reactions of photosynthesis occur here.
7. Stroma- solution surrounding the grana.
a. Calvin Cycle of photosynthesis occurs here.
5. Contain the green pigment Chlorophyll.

19. 1. Organelles such as mitochondria and chloroplasts
may have once been prokaryotes that existed in
a symbiotic relationship with another prokaryote.
a. the inner membranes of mitochondria most
closely resemble the membranes of bacteria.
b. both have their own DNA.
c. shaped like bacteria.

21. 1. Structures in which proteins are made.
a. composed of RNA and protein.
3. Some are attached to membranes for protein export
out of the cell.
4. Some are found free in the cytoplasm to produce
proteins for the cell itself.
6. They are not membrane-bound and are the smallest
of organelles.

23. 1. Manufacturers and shippers of the cell.
2. ER- transports materials thoughout the cells.
a. Rough ER- covered with ribosomes and makes
proteins to be exported from the cell or into cell
membrane.
b. Smooth ER- not covered with ribosomes, synthesizes
steroids in gland cells, regulates calcium levels in
muscle cells, breaks down toxic substances in liver
cells.

25. 3. Golgi Apparatus- modifies, collects, packages and
distributes molecules produced by the cell.
a. appears as a series of flattened sacs.
b. discovered by Italian scientist Camillo Golgi.

27. 1. Small membrane-bordered structures that contain
chemicals and enzymes for digesting materials.
a. formed by the Golgi apparatus.
b. not found in plant cells.
5. Involved in breaking down worn-out organelles.
a. remove “junk” that might clutter up the cell.
3. Used by white blood cells to destroy bacteria.

29. 1. Vacuoles- saclike structures that store materials such
as water, salts, proteins, and carbohydrates.
a. Many plants have a single large central vacuole
which helps support the cell when full.
b. they are smaller and more numerous in animal cells.
7. Plastids- plant organelles that have many functions.
a. storage of food and pigments.
b. leukoplasts store starch granules.
c. chromoplasts store pigment molecules.

33. 1. Composed of a variety of filaments and fibers that
support the cell and drive cell movement.
3. Microtubules- hollow tubules made of proteins.
a. provide support for cell shape.
b. help move organelles.
c. play a special role in cell division by forming
centrioles.
8. Microfilaments- long, thin fibers that function in the
movement and support of the cell.
a. are responsible for cytoplasmic streaming.

35. 1. Cilia- short, hairlike projections from the cell surface.
a. help unicellular organisms move and aid in the
movement of substances along the cell’s surface.
b. smaller and more numerous than flagella.
5. Flagella- long, whiplike structures that help
unicellular organisms move about.
6. Both contain nine pairs of microtubles arranged
around a pair in the center.
a. these microtubles are linked to each other, and
the bridges that connect them generate the force
to produce motion.

38. 1. Diffusion- molecules move from an area of higher
concentration to areas of lower concentration.
a. due to the random motion of molecules.
b. occurs until equilibrium is reached (conc of
the sub is the same on both sides of mem)
c. molecules continue to move but in equal amounts.
2. Biological membranes are selectively permeable.
a. some substances can diffuse through, while others
cannot.

40. 3. Osmosis- Diffusion of water molecules through
a selectively permeable membrane.
a. Osmotic pressure tends to move water
across membranes from a more dilute
solution into a more concentrated solution.
6. Cells almost always have a much lower conc.
of water inside because the cytoplasm is
filled with sugars, salts, proteins, etc.
a. There should be a net movement of water
into a typical cell.
b. If this continues the volume of the cell will
increase until the cell becomes swollen and
bursts like an overinflated balloon. (cytolysis)

41. 1. Cells deal with osmotic pressure in many ways:
a. Some cells never touch fresh water and instead
are bathed in fluids such as blood that have conc
equal to the cells themselves. (isotonic solution)
b. Plants and bacteria have cell walls that prevent
overexpanding
c. Other cells and unicellular organisms pump out
water with contractile vacuoles.
6. Hypotonic solutions- low in solute concentration
therefore water flows into the cell. (freshwater)
7. Hypertonic solutions: high in solute concentration,
water flows out of the cell. (saltwater)
a. cells shrivel (plasmolysis)

43. 7. Facilitated Diffusion- transport of materials with the
conc. gradient by use of carrier proteins.
a. transports larger mol. or those molecules that cannot
dissolve in the lipid bilayer.
b. fast, specific, and does not require energy.
c. Example: glucose-transporter protein helps in the
diffusion of glucose into cells.
8. Passive Transport- transport of materials that does not
require the cell to use energy.
a. example: diffusion, osmosis, facilitated diffusion.
9. Active Transport- movement of materials against the
conc. gradient that requires energy.
a. Integral proteins can pump molecules against the
gradient, such as calcium, potassium, sodium ions.

46. 1. Second type of active transport is when large amounts
of material are transported through movements and
changes in the cell membrane.
a. Endocytosis- taking material into the cell by means
of infoldings or pockets of the cell membrane.
b. Pocket breaks loose and forms a vacuole within the
cytoplasm.
c. Phagocytosis- taking in of large solids or food.
d. Pinocytosis- taking in of liquids.
e. Exocytosis- material inside the cell fuses with the
cell membrane, forcing the contents out of the cell.

49. 1. Cells- smallest unit of life.
3. Tissues- groups of similar cells that perform a similar
funtion.
a. four main types: muscle, epithelial, nerve, connective
3. Organs- groups of tissues that work together to perform
a specific function and help the organ function
successfully.
11.Organ Systems- group of organs that work together to
perform a certain function.