Download 10-4-16 Cells Study Guide - KEY

Pre-AP Biology – Cell Structure and Function Study Guide - KEY
1. Label the following microscopes and know the function of each part. (You do not have to write
the functions for your review, but you will be required to know them for your test.)
1. Body tube, 2. revolving nosepiece, 3-5. objectives, 6. stage clips, 7. diaphragm, 8. light source, 9.
ocular lens, 10. arm, 11. stage, 12. coarse adjustment knob, 13. fine adjustment knob, 14. base
2. What is the cell theory (definition)?
cells are the basic unit of structure in function in all living organisms
3. What are the 3 parts of the cell theory?
All living organisms are composed of one or more cells.
The cell is the most basic unit of life.
All cells arise from pre-existing, living cells.
4. List and define the levels of life’s hierarchy from an atom up to a single organism.
Least specific (biggest thing)
 Organism – Single individual
 Organ System – group of organs working together for a certain function
 Organ – 1 part of an organ system
 Tissue – group of similar cells that do a particular function for an organ
 Cell – Smallest unit of life (All living things are made up of one or more cells) (Can perform all
7 characteristics of MRS. GOCH)
 Organelle – “organ” of a cell
 Molecule – cluster of atoms held together by chemical bonds
 Atom - basic unit of matter made of dense nucleus (protons and neutrons) with electron
cloud around it
Most specific (smallest thing)
5. Answer all of the following questions concerning the 2 cells below.
A)
B)
C)
3mm
1 mm
2 mm
3mm
1mm
2 mm
2mm
3mm
1mm
a. Surface area to volume ratio for each:
i. A: 3:1
SA = 2X2X6 = 24
V = 2X2X2 = 8
24:8 (3:1)
ii. B: 2:1
SA = 3X3X6 = 54
V = 3X3X3 = 27
54:27 (2:1)
iii. C: 6:1
SA = 1X1X6 = 6
V = 1X1X1 = 1
6:1
b. Which cell is most efficient at diffusion nutrients/other essential materials in and waste
out of the cell? C – has the highest surface area to volume ratio
6. Be able to identify all organelles of plant and animal cells and tell their function. Text pgs. 56-57
7. What are the functions of the following organelles? These are only some examples of what
could be on the test. Question #5 tells you that you need to know them all, but this question is
just to ensure that you studying this information.
a. Lysosome – digestion and break down of waste
b. Smooth and Rough ER – in general, transport of proteins through the cell before they are
exported (but there are many more)
c. Ribosomes – site of protein synthesis
d. Peroxisomes – break down oxygen containing waste
e. Nucleus – holds DNA which codes for proteins that will control the rest of the cell
f. Golgi Body – packages and organizes proteins before they are exported from cell
g. Mitochondria – production of ATP
h. Chloroplast – site of photosynthesis (production of glucose) in photosynthetic eukaryotes
8. Be able to identify all the parts of a prokaryotic cell and tell their function (Text pg. 55).
a. What are the only structures in the cytoplasm of a prokaryote? Cytoskeleton, single
circular chromosome (DNA in nucleoid region), ribosomes, protein
b.
9. What is the nucleolus?
Dark spot in nucleus where ribosomes are made. Dark because has DNA and RNA (the rest of
the nucleus just has DNA)
10. What is a nucleoid region? What type of cell has a nucleoid region?
Prokaryotes have a nucleoid region because they do not have a nucleus. It is the area in the
cytoplasm where their DNA is located.
11. What are the 3 types of fiber that makes up the cytoskeleton? Which is the biggest and
smallest?
microtubule (biggest), intermediate filament, microfilament
12. Describe the functions of microfilaments & microtubules. Give an example of where each is
found.
microtubule = INTRAcellular movement (spindle fibers) or whole cell movement (cilia or
flagella)
microfilaments = movement of the entire cell (actin allows you to be active – actin is in
muscle)
13. How are cilia and flagella different?
Both are used for movement. Cilia are short and there are many of them. Flagella are long and
there are only a few of them.
14. What type of cell would each of the organelles be most abundant:
a. mitochondria – Muscles (Anything that would require lots of energy)
b. Rough ER – Pancreas (Anything that secretes something for other cells to use. i.e. Pancreas
secretes insulin and glucagon)
c. Smooth ER – Liver (lots of enzymes in smooth ER so anything that involves breaking things
down)
d. lysosome – white blood cells (lysosomes break down waste and old food. White blood cells
break down pathogens and lysosomes are what actually does this).
15. What is the largest organelle in a plant cell?
Central Vacuole
16. Order cells from largest to smallest (animal, plant, bacteria)
plant (cell wall), animal (no cell wall), bacteria
17. List 3 differences between prokaryotic and eukaryotic cells.
Prokaryotes = no nucleus, no membrane bound organelles, unicellular (most eukaryotes are
multicellular but not all)
18. What are 5 things that all cells must have (prokaryotic and eukaryotic) and why?
DNA – code for proteins
Ribosomes – to make proteins that are coded for by DNA
Proteins – to be the workhorse of the cell
Cell membrane – to be selectively permeable (choose what comes in and out of a cell)
Cytoskeleton – the skeleton of the cell to keep its form and allow movement
Cytoplasm – to be the “filler” material of the cell and to be a location for cell activity to occur
19. How is a cell wall different from a cell membrane (plasma membrane)?
Cell wall is rigid and for protection. Cell membrane is fluid and decides what comes in/out of
the cell.
20. What type of cell has a cell membrane (animal, plant, or prokaryotic)?
Every cell must have a cell membrane
21. What type of cell has a cell wall (animal, plant, or prokaryotic)?
Plants (made of cellulose) and prokaryotes (not made of cellulose) – Animal cells do not need
cell walls because it would limit their mobility
22. Does a plant cell have mitochondria? Why?
Yes, even though they have chloroplast to make their own glucose they must still convert that
glucose to ATP.
23. What is the function of a glycoprotein (found in the cell membrane)?
I.D. badge – identify the type of cell to recognize yourself from an invader and for cells of the
same type to join together in tissues
24. Where are ribosomes made? Where are they found? What do they make?
nucleolus; cytoplasm or rough ER; proteins
25. How does food within a food vacuole get digested?
Lysosome
26. What is apoptosis?
programmed cell death (to kill diseased cells or during development – like in between your
fingers and toes)
27. What are 3 organelles found in a plant cell and not an animal cell?
chloroplast – photosynthesis to make glucose
central vacuole – store water
cell wall – made of cellulose and used for extra protection
28. What are 2 structures found in animal cells not found in plant cells?
centrioles and lysosomes
29. Why does a plant wilt?
central vacuole loses water
30. What is endosymbiosis?
creation of eukaryotes from prokaryotes (specifically mitochondria and chloroplast).
Larger prokaryotes engulfs smaller prokaryote --- both benefit (small gets protection and big
gets energy from small) ---- remain together during asexual reproduction (binary fission) --become 1 organism
31. List 3 pieces of evidence that supports endosymbiosis.
Mitochondria and chloroplast both have:
1) their own DNA
2) their own ribosomes that are smaller (like prokaryotes)
3) both divide by splitting in 2 (like binary fission)
4) both have 2 membranes
Cell Membrane and Transport Section:
32. Define:
a. Concentration –
amount of solute / amount of solvent
b. Concentration gradient differing concentrations across a cell membrane
33. What does the “fluid mosaic model” explain?
Fluid – cell membranes actually move because of the unsaturated fatty acid tails
Mosaic – cell membranes are made of many different parts (phospholipids, proteins,
cholesterol)
34. List 4 functions of proteins found in the cell membrane.
Enzymes – speed up reactions
Glycoproteins – I.D. badges
Receptor proteins – receive signals from outside the cell
Transport proteins – move larger or polar solutes into and out of the cell
35. What do glycoproteins and glycolipids do, and why are they important to the immune
system?
I.D. tags (Cell recognition); Let your body tell the difference in your cells and bacteria/viruses
36. Define the following terms:
a. permeable
things can come and go
b. impermeable
things can’t come and go
c. selectively permeable
Small, nonpolar molecules can cross directly through the phospholipid bilayer. They is
because they are small enough to fit in between the phosphate heads and they are
nonpolar (so they can mix with the nonpolar tails).
Polar molecules cannot cross because they cannot mix with the nonpolar tails. Large
molecules cannot cross because they cannot fit between the phosphate heads.
37. Why do receptor proteins have a shape that fits a specific messenger?
Each receptor protein will only receive 1 kind of messenger. This allows the body to know
that when it releases a message that it will only be picked up by the cells that need it.
38. How does a glucose molecule cross the cell membrane? How about ions?
Through transport proteins (both are large and have charges)
39. What is a “concentration gradient” and what is going “down or with” it and going
“against it”?
Difference in concentration across a cell membrane.
Going down the concentration gradient = going from high to low
Going against concentration gradient= going from low to high
40. What does tonicity refer to?
The ability of a solution to make a cell gain/lose water
41. Explain the movement of water if a cell were placed in a…
Hypertonic – Water leaves the cell (cell shrivels up like a skinny hyper kid)
Hypotonic – Water enters the cell (cell swells up like a fat hippo)
Isotonic – Water enters and leaves at the same rate
42. What type of solutions do plant & animal cells prefer?
plants = hypotonic (so they can gain water and be turgid – they have central vacuoles to store
water)
animals = isotonic
43. If an animal cell is placed in a hypotonic solution for too long, what will happen to it?
What prevents a plant cell from doing this?
Animal cell would lyse (burst). Plant cell has a cell wall that resists pressure (and a central
vacuole to store water)
44. Define the following terms:
a. flaccid - limp
b. lysis – to burst or rip
c. turgid – full, stiff
d. plasmolysis – cell membrane ripping away from the cell way
45. If solution A has a higher concentration of solute than solution B, what will move (solute
or water) and which direction if diffusion is occurring?
From A to B (it will go down it’s concentration gradient – more solute in A than B
46. If solution A has a higher concentration of solute than solution B, what will move (solute
or water) and which direction if osmosis is occurring?
From B to A (water will go down its own concentration gradient – there is more water in B
than in A)
47. Using the diagram above, answer the following questions (answer by saying left or
right):
a. Which side is hypertonic? right
b. Which side is hypotonic? left
c. Which direction would diffusion occur? right to left
d. Which direction would osmosis occur? left to right
48. List 2 differences between active & passive transport.
Passive = no energy (ATP) and down the concentration gradient
Active = energy (ATP) and up the concentration gradient
49. List and define the 3 examples of passive transport.
Diffusion – movement of small, nonpolar molecules directly across the phospholipid bilayer
going down their concentration gradient
Facilitated Diffusion – movement of larger or polar molecules across transport proteins going
down their concentration gradient
Osmosis – movement of water through aquaporins (transport proteins for water) going down
its own concentration gradient (will be the opposite direction of diffusion)******
50. Give 2 similarities and 1 different between diffusion and facilitated diffusion.
Both require no energy because they are going down their concentration gradient
Diffusion occurs directly across the phospholipid bilayer where facilitated diffusion occurs
through transport proteins
51. Give 1 similarity and 2 differences between facilitated diffusion and active transport.
Both use transport proteins
Differences = facilitated diffusion requires no energy and goes down its concentration
gradient while active transport requires energy and goes against the concentration gradient
52. Answer the following questions about vesicular transport (also called bulk transport).
a. Why do some molecules have to use vesicular transport (bulk transport –
endocytosis and exocytosis) to enter or leave the cell? In other words, why can’t
these materials move through the phospholipid bilayer or transport proteins like
other solutes?
The molecule is too big to fit through a transport protein (For example, if a protein is
coming into or out of the cell then it would be too big to fit through another protein)
b. This type of transport uses what to move materials into/out of the cell?
Vesicles
c. Define endocytosis and exocytosis.
Endo – using a vesicle to bring material into the cell
Exo – using a vesicle to take material out of the cell
d. Define the 2 different types of endocytosis.
Phagocytosis – “cellular eating” A cell engulfs a particle by wrapping extensions called
pseudopodia around it and packaging it within a vacuole.
Pinocytosis – “cellular drinking” A cell gulps droplets of fluid into tiny vesicles.
53. A cell that has a concentration of 2 M is placed in the following solutions and the percent
change in the mass of the cell was recorded. Use the chart to answer the following questions:
Concentration of solution
Percent change in mass
(Molarity)
0
+23%
2
0%
4
-20%
a. Which concentration is:
a. hypertonic? 4
b. isotonic? 2
c. hypotonic? 0
b. Explain why:
a. the cell gained mass in the 0 M solution - hypotonic solution so water came in
b. had no change in mass in the 2 M solution – isotonic solution so no change in
water
c. lost mass in the 4 M solution – hypertonic so water came out
54. Be sure to be able to identify and explain the functions of all of the components of the
cell membrane. Use diagram to the right.
A = carbohydrate
B = glycoprotein
C= glycolipid
D = integral protein
E = ECM (extracellular matrix)
Ab = phospholipid head
Ac = cytoskeleton
Ad = cholesterol