Cells
Organelles
Passive Transport
Active transport
Cell Membrane
100
List and describe the two types of cells.
Eukaryotic= more complex, nucleus, linear DNA, membrane bound organelles
Prokaryotic= simple, no nucleus, circular DNA, lacking membrane bound organelles
100
What is the function of the cell membrane?
determines what enters or exits the cell
100
What is passive transport?
1. no energy needed
2. materials move from an area of high concentration to low concentration
100
Define active transport
Molecule move from an area of low concentration to high concentration and require the use of energy (ATP).- molecules move up the concentration gradient.
100
Explain why the cell membrane can also be called the "fluid mosaic model".
The membrane is composed of many smaller parts such as lipids, phospholipids, proteins and carbohydrate chains. A mosaic is composed of many small parts as well.
200
Identify the prokaryotic and eukaryotic cell
A= prokaryotic
B= eukaryotic
200
What is the function of the lysosomes?
Contains digestive enzymes which will breakdown molecules
200
What are the three types of passive transport discussed in class and explain the difference between the two.
1. Diffusion- movement of molecules from high to low
2. Osmosis- the diffusion of water across a semi-permeable membrane
3. Facilitated diffusion: using protein channels to move molecules that are too large or too charged to pass by simple diffusion.
200
Explain the process of endocytosis and exocytosis.
Endocytosis is the cell bringing a molecule (particle) INTO the cytoplasm and exocystosis is the cell bringing a molecule (particle) out of the cytoplasm.
200
Explain the structure of a phospholipid and any special characteristics of each.
(Glycerol with a phosphate) head= hydrophilic
Fatty acid tail (two) = hydrophobic
300
What is the cell theory?
1. all cells come from pre-existing cells
2. cells are the basic unit of structure and function of living things
3. all living things are made up of one or more cells
300
Explain the function of the nucleolus and the chromosomes. Identify the location of each in the eukaryotic cell.
Found inside the nucleus.
nucleolus produces ribosomes and the chromosomes carry the organism's genetic information.
300
Define the following terms: solute, solvent and solution
solute= the material being dissolved
solvent= the material doing the dissolving (i.e. water)
solution- the combination of both solute and solvent
300
Explain the two types of endocytosis and describe the process.
Types: phagocytosis (large solid molecules) and pinocytosis (molecules dissolved in liquid)
The cell will surround and engulf the particle and completely surround it. The cell membrane will then fuse together and form a vesicle.
300
Where would the components of the cell membrane be synthesized in the cell.
rough ER= proteins
smooth ER= lipids
400
If viewing a cell under a microscope, how would you be able to identify the cell as either a plant or animal cell.
Plant- square, cell wall, LARGE central vacuole and chloroplast
animal cell- round, small vacuoles (if any)
400
Explain how a disturbance in the mitochondria might impact the cell and ultimately the organism. Explain how the organelles are related to the function of an organism.
organelles make cells; cells make tissue; tissue makes organs; organs make organ systems and organ systems make organisms...if there is a malfunction on a cellular level it will impact the organism since cells are the foundation of living processes for all living things.
400
Explain how the concentration of solute outside the cell will determine the direction of osmosis either into or out of the cell.
Hypertonic = high solute concentration and low water concentration OUTSIDE the cell compared to the concentrations INSIDE the cell will cause water to flow OUT of the cell and the cell to shrink.
Hypotonic= low solute concentration and high water concentration OUTSIDE the cell compared to the concentrations INSIDE the cell will cause water to flow INTO the cell and the cell to swell.
isotonic= equal solute concentration and equal water concentration OUTSIDE the cell compared to the concentrations INSIDE the cell will cause no net gain of water either into or out of the cell.
400
Explain the process of exocytosis.
Vesicles are filled with molecules in the inside of the cell and then fuse with the plasma membrane and deposit the molecules outside the cell.
400
Why are there surface proteins and trans-membrane proteins?
Some of the "R" groups on the various amino acids will cause portions of the protein to be either hydrophobic or hydrophobic. Therefore some of the proteins will orientate themselves in the hydrophobic region and others in the hydrophilic region. Others will simply sit on the surface since they are hydrophilic.
500
Describe what is happening to the cells in the image below. Be sure to mention all organelles and concentrations involved.
cell was placed in a hypertonic solution and water is diffusing out of the cell through the process of osmosis.
500
Compare the cell to a factory. Which organelles would be the following parts of a factory. The boss, the workers, the power center, the shipping department, the recycling center and the factory floor. Explain why for each.
boss=nucleus- controls all the activities in the cell/factory
workers= ribosomes- makes the proteins/products for the factory/cell
power center= mitochondria= supplies energy to the cell/factory
shipping department=Golgi apparatus= prepares product/molecules for export from the factory/cell
recycling center=lysosomes= breakdown and recycles materials in the cell/factory
factory floor=cytoplasm= allows for movement of materials throughout the cell/factory
500
Indicated what type of passive transport would be used to move the following molecules across the cell membrane: glucose, large molecule and water
simple= glucose (small enough to pass through)
facilitated= large molecule = due to either the size or charge of the molecule
water= osmosis = water is the molecule
500
What type of transport is represented and why?Active transport: energy is being used and molecules are moving from low to high concentration.
500
Explain how the 4 types of proteins found in the cell membrane and the function of each. Explain how the lipids found within the cell membrane are help in place.
What other molecules are found in the membrane?
lipids held by hydrophobic interactions.
1. receptor protein= bind to external chemicals in order to regulate processes within the cell.
2. recognition proteins= fingerprint for cell; used to recognize the cell by other cells
3. transport proteins= passageway for molecules
4. enzymatic proteins= speed up chemical reactions
5. carbohydrate chain= I.D. tag
6. cholesterol= gives flexibility to the membrane