What are the 3 parts to the cell theory?
1) All organisms are composed of one or more cells
2) The cell is the basic unit of all living organisms
3) Cells cannot be created, but come from existing cells (mitosis)
What are the four types or microscopes?
Light microscope
SEM- Scanning electron microscope
TEM- Transmission Electron Microscopy
Synchrotron
How much bigger you can make an object appear dependent upon the lens system:
a) Magnification
b) Resolution
c) View
d) Contrast
a) Magnification
The ratio between the image and the specimen’s actual size
Inside or outside of the cell, type of light:
a) Magnification
b) Resolution
c) View
d) Contrast
C) View
Ones darker then the other, stands out from the background:
a) Magnification
b) Resolution
c) View
d) Contrast
d) Contrast
Define Resolution
What is it dependent upon?
Measure the clarity of the image or the ability to differentiate between two dots
Dependent upon the wavelength of the light used
Seeing a car from far (looks like one head light), as it gets closer you can see there are two headlights.
This is an example of what?
Of resolution.. The ability to distinguish as seperate objects
Which type of light will provide better resolution?
Red or Blue?
Blue because it has a shortwe wavelength then red
Light microscope:
- Used ___ light and simple lenses to see ____ objects
- Magnification =
- Resolution=
- Uses ____ for illumination
- ___ versatile
- Visible light, Small objects
- 1000x
- 0.2µm
- light
- very versatile
Light micrograph:
- Uses properties of ___ and ______
- Most animal cells are _____
- Euglena is a photosynthetic microbe with ______
- Light and chromophores
- colorless
- chlorophyll
What type of cells use a cell plate when dividing?
Plant cells
What are dyes and protein fluoresce used with microscopes for?
Used to give off light when light is shone on them, allow us to see particular parts of the cell
TEM:
- Uses an ____ beam
- Magnification =
- must have ___ and very ____ sectioned samples
- _____ resolution
- ____ versatile
- Shows contrast with ___ + _____
- electron beam
- >100 000x
- fixed and very thinly
- high resolution
- less versatile
- Led and metal
How do we provide contrast for TEM?
Heavy metals are used as general stains, attached to the macromolecules
SEM:
- Objects are coated with an electron dense material often ____ or ______
- what part of the cell is visualized?
- Lead or gold
- only the surface
What is GFP?
Where was it first isolated from?
Which microscope allows us to see GFP?
- It is a green fluorescent protein used to track things in organisms in order to see it more clearly
- from a jellyfish
- Fluorescence microscope
How did they contribute to GFP?
- Osamu Shimomura
- Douglas Prasher
- Roger Tsien
- Isolated the GFP protein from jellyfish
- had the idea to create GFP fusion protein to use in other types of cells (clone)
- Made great advances in our understanding of how protein chemistry affects fluorescence of GFP
What are traits of Prokaryotes? (5)
- ______ OR ______
- Have a _____ _______ organization
- Lacks a ____________ ________
- _______ microorganisms of ____ size
- No _______ _________
- Divide by _______
- Bacteria OR Archaea
- Have a simple structural organization
- Lacks a membrane - enclosed nucleus
- Unicellular microorganisms of small size
- No subcellular compartments
- Divide by binary fission
What are Eukaryotes?
- ______ or _____ cell
- _____ evolutionarily advanced= more ____ _______
- Have _______
- Have more _____ and ________
- can carry out ____ ____ _______
- _____ cell size = more extensive use of _______
- Divide by ______
- Animal or Plant cell
- More evolutionarily advanced= more complex internally
- Have a nucleus
- Have more organelles and compartments
- can carry out specialized chemical reactions
- Larger cell size = more extensive use of membranes
- Divide by mitosis
What is the plasma membrane?
The border between a cell’s exterior and its interior
What is a phospholipid bilayer?
What are the two parts ?
Which one likes water?
Creates a barrier that encloses the cytoplasm
Hydrophilic head - likes water
Hydrophobic tail - hates water (so it hides in the middle)
What is the cytoskeleton? and where is it located?
- Located in the cytoplasm of a cell
- Forms structures such as flagella, cilia and lamellipodia
- Plays important roles in both intracellular transport (the movement of vesicles and organelles, for example) and cellular division.
What are te 3 types of cytoskeleton?
1) Microtubules
2) Intermediate filaments
3) Microfilaments
What does this in the cytoplasm?
- Cell shape
- Chromosome sorting
- Organelle positioning
- Cell motility
- Internal structure of cilia and flagella
- Long, hollow cylindrical structure about 15 nm in diameter
- Composed of protein tubulin
Microtubules
What does this in the cytoplasm?
- Cell Shape
- Mechanical strength
- Anchor cell membranes
- Only in multcellular organisms
- Help maintain shape and rigidity
- Bind in stagered array to form a twisted rope like structure of 8-12 nm
Intermediate Filaments
What does this in the cytoplasm?
- Cell Shape + Strength
- Muscle contraction
- Movement (amoeba)
- Intracellular transport
- cytoplasmic streaming
- Made up of two strands of actin (5-7 nm)
- Near plasma membrane
Microfilaments
OR
Actin Filaments
Microtubules can only grow from ____ end, and shrink from ____ end
one end
either end
What is Cytoplasm?
In the interior of the cell, the space between mitochondria and ribosomes
Define Ribosomes
Ribosomes are vey large complex cellular machines that are made from RNA and proteins
What is the function of Ribosomes?
- function is to interpret the genetic code and make proteins by combining amino acids in the correct sequence
T or F: Ribosomes are organelles
False;
They are enzymes, big enough to see with TEM
Where are ribosomes found?
Floating freely in the cytoplam, or attached to the membrane of the endoplasmic reticulum (ER)
Ribosome subunits:
In Prokaryotes?
In Eukaryotes?
- Prokaryotes: large subunit= 50S
Small subunit = 30S
Overall = 70S - Eukaryotes: large subunit =60S
Small subunit = 40S
Overall = 80S
What does the “s” stand for with ribosomes?
Why don’t the subinit sizes add up?
’s don’t add up because sedimentation is dependent on weight and shape
S = Svedberg Units
Which 2 things have their own ribosomes?
What kind of ribosomes?
Chloroplasts and mitochondria have their own ribosomes of 70 S ribosomes
Define the Nucleus
What can it be compared to?
The Nucleus contains the cell’s genetic material (DNA).
It can be compared to a library (not a brain) becuase it is not actually thinking, the information is just stored there and can be taken out.
Define Nucleolus:
Small structure inside the nucleus
It is the site of ribosome assembly
normally only one, unless if the cell is rapidly growing
RNA transcribed inside the nucleus is exported to the cytoplasm through _______
They act as a _____ allowing only specific materials in and out of the __________
Nuclear pores
Gateway, nuclear envelope
Define : Smooth ER
- Smooth network without ribosomes
- Concerned with lipid metabolism, carbohydrate metabolism, and detoxification
- Breaks down tylenol
Define: Rough ER
- Studded with ribosomes
- Usually closer to the nucleur then the SER
Sorts proteins to their appropriate compartment:
- Protein synthesis
- Protein modification
- Protein folding
In what types of cells would you expect to find large amounts of Smooth ER?
Animal cells
If you found a new type of cell contained large amounts of rough ER what might you conclude?
They will be muscle cells or fat cells
Define cell wall
Provides support and protection for the plasma membrane and cytoplasm
Define glycocalyx
Outter gelatinous covering, that protects bateria from drying out by trapping water
Define Capsule
Very thick gelatinous glycocalyx used as a defence system
Define Phili
Filamentous structures extending from the cytoplasm outwards
Short and numerous
Allow Prokaryotes to attach to surfaces, and each other
Define Flagella
Flagella : long (threadlike) appendages on the surface of the living cell
- Eukaryotic and Prokaryotic cells
- Move slow
Define Cilia
Short (hair like) appendages extending from the surface of the cell
- Eukaryotic cells
- Short and move fast
- Cover most of the cell’s surface
Define Organelle
examples?
aggregate of macromolecules or membrane bound compartments with its own structure and function
- Ex. Ribosomes, cell wall, Pili, flagella
What consists of a stack of flattened membranes, each enclosing a single compartment?
How and where is the material transported?
The Golgi;
transports material from ER to other parts of the cell via membrane vesicles
Cis Golgi =
Trans Golgi =
Medial Golgi =
-Close to the ER membrane
(where material enters)
- Near the plasma membrane
(Where the material exits)
In the middle
What are the 3 functions of the Golgi?
1) Processing - modify proteins and lipids
- transported via vesicles from ER to cis Golgi
2) Sorting - proteins enter Golgi from ER, then directed to a location
3) Secretion - packages different types of materials into secretory vesicules, that later fuse with the plasma membrane.. releasing its contents outside the cell
How many Golgi’s in a cell?
Also referred to as a ..?
Animal cell = 1
Plant cell = many
**Post office ( sorts stuff out, sends it where it needs to go)
T or F: The Golgi is directly linked to the ER
False;
Not directly linked to the ER, transport occurs in vesicules
What are vesicles?
Vesicles are balls of lipids and proteins, that are in the cell and transport things where they need to be.
- Organlles for cytoplasmic transport
How do vesicles form?
Buds from on the inside of the membrane, then pinch off blobs(vesicles) that then float away
Why are vesicles important?
What do they transport?
They transport stuff in(Endocytosis) and out(Exocytosis) of the cell
They transport lipids to the plasma membrane from the ER
Lysosome:
- A ______ compartment
- Produced by ____ and _____
- Digests _______ ________ _______
- Digests ______ ingested by the cell by ______
- A digestive compartment
- Produced by RER and Golgi
- Digests damaged cellular components
- Digests particles ingested by the cell by endocytosis
The ____ provides the digestive enzymes
The ____ activates the enzymes and packages them safely into ______
- RER
- Golgi; lysosomes
A food vacuole forms when..?
When material is brought into the cell by endocytosis combines with a lysosome
Define: Chloroplasts
- A green, light absorbing organelle of plants and algae where photosynthesis occurs
- The most important organelle
- Make their own membrane and lipids (throught its internal structure)
Can a cell create chloroplasts and mitochondria?
No, they are passed on from cell to cell
What has their own DNA, and can make their own RNA and proteins? And also has 70S ribosomes?
Chloroplasts and Mitochondria
What are other types of plastids? (4)
1) Proplastid
2) Etioplast
3) Amyloplast
4) Chromoplast
Etioplast of dark grown plant
- Colorless chloroplast
- distinctive checker board in the middle
- The stem continues to grow very tall in the dark, once it is exposed to light the leaves then start to grow
Amyloplast:
- __________ _______ found in some ______ cells
- Responsible for the _______ and storage of ______ _____
- We use _____ to increase their contrast
- non-pigmented organelles found in some plant cells
- Responsible for the synthesis and storage of starch granules
- We use a dye to increase their contrast
Chromoplast:
- Store pigment in ____ and _____
- In ____ cells
- No _______
- Store pigment in fruits and flowers
- In plant cells
- No chloroplasts
When a fruit or a vegetable ripens, the conversion from ______ to ______ occurs
Conversion from chloroplasts to chromoplasts occurs
What has two membranes and a matrix in its internal structure?
Mitochondria;
Inner and outer membranes
Matrix inside the inner membrane
________ cells have many mitochondria with more Cristae
Muscle cells
Plant cell mitochondria are located close to the _____ to allow ______ ______
chloroplasts
metabolic exchange
Vacuole:
“___ _____”
- Contains ____ or _____ substance
- Made from the ____ of many sm _____ ______
- Prominet organelle in _____ cells
- Temporarily stores or transports substances in ______ cells
“Empty space”
- Contains fluid or solid substance
- Made from the fusion of many sm membrane vesicles
- Prominet organelle in plant cells
- Temporarily stores or transports substances in animal cells
Vacuole in plant cells?
Maintains cell shape and turgor pressure (keeps crisp)
Full of water
Majority of the cell volume
Can also act as garbage can
What do food vacuoles do?
Carry objects from the cell membrane and protect the rest of the cell from digestive enzymes
What is cell fractionation?
It is the process or isolating different parts of the cell from each other
How does centrifugation work?
It spins tubes slowly to start, which will bring the large components of the cell to the bottom to settle.
It then starts to increase speed as the smaller objects are still left
it seperates objects based on their density
What does centrifugation allow us to do?
Study organelle function in isolation
Identify macromolecule content
T or F: all the cells in an organism have the same DNA
True
Can a plasma membrane be digested by an enzyme?
Yes, they can basically digest anything
T or F: Chloroplast is bigger then mitochondria
True
Which type of cell has what?
Prokaryotes vs eukaryotes
- Organelles
- DNA
- Ribosomes
- Cytoskeleton
Prokaryotes: DNA + Ribosomes
Eukaryotes: Organelles, DNA, Ribosomes, Cytoskeleton
What type of cell has what?
Animal Vs Plant cells:
- organelles
- cell wall
- central vacuole
- centriole (cylindrical structure)
Plant: Organelles, cell wall, central vacuole
Animal: Organelles, centriole
Whats the difference between exocytosis and endocytosis?
Exocytosis - transport material out of the cell
Endocytosis - materials are brought into the cell inside a vesicle