[Mon]

I tried to look for the answers to the questions in my biology book, but I could not find them. I found the answers to half of the questions in my notes and a few in the book, but the rest I could not find. I know my book talks about the keywords in the questions that I am looking for an answer to, but I could not understand which was the correct answer to write down or not. I do not want to be studying an answer to a question that I find out is wrong. My weakness is finding an answer to a question that is not word for word. For example: One of the questions I am having trouble finding the answer to is "Which transport methods require an energy expenditure by the cell?" I went to the section in my book about it, but could not find an answer that has "require an anergy expenditure by the cell" in any of the sentences. I have trouble with reading comprehension (had trouble all my life) and the only way I could find answers is through most of the question being in the sentence. My first exam is not until 24th of this Month and there is a lot of information to cover. I want to make sure I study all the material from the previous week and know them before I get more information to study.

Here are the questions... (I also have some answers I am not sure is correct, so let me know if they are right or not. There are quite a few that I did not know what answer put down at all)

1. Distinguish between a glycoprotein and a glycolipid. Which side of the cell membrane do they occur on?

My answer:
Glycoprotein - attached to proteins        Glycolipids - attached to lipids

That's the answer to the first part of the question (what I found in my notes), but the side of the cell membrane they occur on was not in any of the sentences. However, I did take a look at the cell membrane figure in the book and it shows the Glycoprotein occuring on the top left and Glycolipid occuring at the bottom left. Is that the answer to the question, or should it be answered differently?


2. What is the role of cholesterol embedded in the cell membrane?

My answer:
by regulate memberane fluidity
- Cholesteral molecules are there to keep the texture constant.

My answer was found in my notes, but I don't understand the word "fluidity".


3. How are simple diffusion and facilitated diffusion similar and different?

My answer: (not sure if the similar part is correct or not, but I am pretty sure the difference answer is correct.
Similar - Both move from crowded areas to less crowded areas
Difference - Facilitated diffusion requires a protein channel and Simple diffusion does not require a protein channel.


4. Give an example of molecules that move into or out of the cells by simple diffusion? Give an example of molecules that move into or out of the cells by facilitated diffusion.

My answer:
Simple Diffusion - molecules that are larger than oxygen
Facilitated Diffusion - protein channels

I don't think these are correct, but it has "move into" or "move out of" in the sentences in my book. There were a few different with the move into or move out of in sentences for this section, but I chosed what I thought might of been right?


5. When is active transport required to move molecules into or out of the cell?

No answer to that one because I could not find anything in the sentence with "required to move molecules into or out of the cell". Anyone know?


6. Which transport methods require an energy expenditure by the cell?

My answer:
Active Transport

Is this correct?



7. If potassium ions (K+) are dissolved in water, and placed inside a cell membrane, which molecule(s) will pass across the cell membrane?

My answer:
Electrochemical gradient

Is this correct? I could not find anything in my notes or book with (K+) in the sentences, so I looked online at yahoo and this is all I could find that may be the answer?


8. Be able to predict direction of water movement based on solute concentrations inside and outside the cell.

I don't have an answer because I have no idea what it is or understand it. I looked online and wrote the whole question in, but could not find a sentence with "prediction direction of water movement based on solute concentrations inside and outside of cell". Anyone know?


9. Distinguish between endocytosis, pinocytosis, and exocytosis. Give an example of molecules that are transported using these methods.

My answer:
I put the definitions as my answer, but I don't think that's what the question is asking? I don't really understand the definitions except for "pinocytosis", which is "cell drinking". I could not find no examples because the book did not say the word "examples" anywhere or "for instance". I need help on this one.


10. Genetically programmed cell death is called what?

My answer:
Necrosis or apoptosis

Is that correct? I typed in the question online at yahoo and this is what I found. I am pretty sure this is right and what the question is looking for, but I want to make sure.


11. How does a non-duplicated chromosome compare physically to a duplicated chromosome?

No answer because I could not find "non-duplicated chromosome compare physically to a duplicated chromosome" in the book or online. Anyone know this one?


12. Why do you think DNA cooils tightly into chromosomes before mitosis occurs?

I do not understand this question. Anyone willing to explain it, so I can answer it? I know I have to answer it because "why do you think" is at the beginning of the question.

13. What directs the movement of chromosomes during the division process?

My answer:
pieces of DNA

I am just guessing. Is that right?


I have a total of 25 questions, but I know the ones that I did not post here are for sure correct (obvious in my notes and book and easy to understand). I hope this is not too many questions. A few I had no idea about (could not find a dirrect understanding answer) and a few I am not sure the answer is right or not.

I hope to hear from you guys soon, so I can start studying the ones I am having trouble with. The study guide questions are very important because its to help me understand the subject and important biology words for the first exam. I can ask the teacher on Monday the questions that I am not sure about or do not have an answer to that are not answered on here. I hope to get some answered on here though (especially the ones I have no answer at all to), so it will be less questions to ask the teacher on Monday.

[xxabcxx]

i'll post some answers

#2: Fluidity means keep it in a fluid state.  So cholesterol is to keep this fluidity, because under cold temperature, the membrane could solidify, which is not a good thing. 

#3: simple diffusion is passive going through the membrane, while facilitated diffusion is with the use of channel, or transporter.

#4: simple diffusion: O2
     facilitated diffusion: Not sure if glucose is one.

#5: when transporting molecules against the gradient

#6: Active transport

#10: apoptosis

[Padfoot]

You shouldn't be scanning your text for exact phrases, you should look up the key terms in the index of your text.  Eg - for Q1, look up glycoprotein and glycolipid.  For questions like 'what is the role of cholesterol embedded in the cell membrane', find out about cell membranes - Wikipedia is your friend here.
This also applies for a lot of your other questions. 

13. mitotic spindle (microtubules)

5.  xxabcxx is correct - and it is it's electrochemical gradient
In this case it would have been wise for you to look up 'active transport'.

6. is correct

7. (If potassium ions (K+) are dissolved in water, and placed inside a cell membrane, which molecule(s) will pass across the cell membrane?)
Correct, it would depend on the electrochemical gradient 

8. (Be able to predict direction of water movement based on solute concentrations inside and outside the cell.)
Water will move from area of low solute concentration to area of high solute concentration (untill = concentrations of water on both sides)

12) (Why do you think DNA cooils tightly into chromosomes before mitosis occurs?)
I would say for organisation and space for mitosis - hopefully someone else can verify this though

Hope that helps!  Maybe someone else will give you a hand with the rest - You can probably find them yourself though...

[Sev]

1. A glycoprotein is a protein covalently attached to a carbohydrate.  Likewise a glycolipid is a lipid/carbohydrate complex.

Glycolipids are on the outside of the cell membrane (they function in cell to cell communication)

2. cholesterol is a 'temperature buffer'.  'fluidity' refers to how 'fluid' the membrane is (the membrane is not static, the phospholipids are constantly switching positions).

3. you're right for both.

4. generally small or lipophillic (hydrophobic) molecules can cross via simple diffusion - eg.ethanol.
As for facilitated diffusion, water often crosses via protein channels called aquaporins.

5. Active transport is nessesary in moving molecules against their gradient.  An example is Na+/K+ ATPase (Sodium-Potassium pump) which actively transports both Na+ and K+ against their gradient.

9.  Exocytosis is the process by which large molecules are exported out of the cell (the molecules are packaged inside a vesicle which subsequently fuses with the membrane).  Endocytosis is the reverse process.  Pinocytosis is a type of endocytosis (where the vesicle buds from an invagination in the membrane)

10. yes...Apoptosis.  

11.  Hard question to answer.  In my opinion both are just a tangle of chromatin.

12. I would guess to make it easier to separate sister chromatids at the metaphase plate.

13. Motor proteins and microtubules of the spindle apparatus.

[Yggdrasil]

1. Distinguish between a glycoprotein and a glycolipid. Which side of the cell membrane do they occur on?

My answer:
Glycoprotein - attached to proteins        Glycolipids - attached to lipids

That's the answer to the first part of the question (what I found in my notes), but the side of the cell membrane they occur on was not in any of the sentences. However, I did take a look at the cell membrane figure in the book and it shows the Glycoprotein occuring on the top left and Glycolipid occuring at the bottom left. Is that the answer to the question, or should it be answered differently?

This should probably be obvious but you might want to mention that glycoproteins and glycolipids are proteins/lipids which have been attached to sugars/oligosaccharides.  The carbohydrate chains generally occur on the extracellular side of the plasma membrane.  I'm not entirely sure for the reason, but I think one reason may be to help solvate the cells better.  Also, glycans play important roles in communicating with other cells and are imporant structural components of the extracellular membrane

2. What is the role of cholesterol embedded in the cell membrane?

My answer:
by regulate memberane fluidity
- Cholesteral molecules are there to keep the texture constant.

My answer was found in my notes, but I don't understand the word "fluidity".

The plasma membrane can be thought of as something like a liquid, and like most liquids, membranes can freeze.  Freezing is of course bad for the cell because membrane-bound components need to be able to move around for the cell to function properly.  Cholesterol helps to lower the freezing point of the membranes, helping maintain the fluidity of the membrane at low temperatures.

Too much fluidity can also cause problems.  Strangely enough, cholesterol also acts to reduce fluidity at high temperatures.  Thus, cholesterol seems to widen the range of temperatures at which the membrane will function properly.

3. How are simple diffusion and facilitated diffusion similar and different?

My answer: (not sure if the similar part is correct or not, but I am pretty sure the difference answer is correct.
Similar - Both move from crowded areas to less crowded areas
Difference - Facilitated diffusion requires a protein channel and Simple diffusion does not require a protein channel.

Absolutely correct.  A more scientific way of stating the similarity is to say that both move molecules along their concentration gradient.

6. Which transport methods require an energy expenditure by the cell?

My answer:
Active Transport

Is this correct?

Correct.

10. Genetically programmed cell death is called what?

My answer:
Necrosis or apoptosis

Is that correct? I typed in the question online at yahoo and this is what I found. I am pretty sure this is right and what the question is looking for, but I want to make sure.

Apoptosis is programmed cell death.  Necrosis, while it is cell death, is not programmed cell death.


I may try to answer some of the other questions later, but I would try rereading the entire sections (i.e. don't skim over stuff looking for key words) on osmosis, exocytosis/endocytosis/pinocytosis, and mitosis.  If your book isn't helpful, the wikipedia articles on the topics may help:

http://en.wikipedia.org/wiki/Osmosis
http://en.wikipedia.org/wiki/Exocytosis
http://en.wikipedia.org/wiki/Endocytosis
http://en.wikipedia.org/wiki/Pinocytosis
http://en.wikipedia.org/wiki/Mitosis

[edit: sev beat me to the reply, but I'll still post these answers]

[Mon]

thanks guys! and thanks for the wikipedia links. I did go to wikipedia and found a few answers, but some I could not understand fully to find the right answer. You guys defiantly help a lot.

Questions 11 and 12 I will ask the teacher on Monday about those because no ones really sure and it is a hard question to answer.

When I get my next set of study guide for this upcoming week and if I have any questions I have trouble understanding and finding an answer to, I will ask you guys (hopefully in this thread) at the end of the week. It's hard to answer a question and especially find the answer to the question if I do not understand what the question is trying to ask to find the information I really need to be looking for to answer the question correctly. Wrong answers come from missunderstanding the question (not understanding it correctly or at all).

You guys are awesome. =)

[Yggdrasil]

I'm not sure about 11, but the answer to 12 is as follows:  packaging the chromatin up into chromosomes helps the cell move it more efficiently.  For example, if you had to move a 12 foot extension cord to a new appartment, you would first wrap it up into something more compact instead of just dragging the cord along.  Condensing the chromatin into chromosomes also allows the chromosomes to align at the metaphase plate, which is an important checkpoint in mitosis.

[Mon]

Questions on study guide 4...This time I was able to find an answer for all of them, but some I did not understand very well or may be wrong. I am only going to post the ones that I am not 100% sure of the answers.

Energy
1.   In order to synthesize ATP from ADP and Phosphate, what is required?
*My answer: food/energy

2.   What are two possible sources of energy used in the synthesis of ATP?
*My answer: food/sun

3.   What is a waste product of any energy transformation?
*My answer: Makes the universe less organized and more disordered (requires order to be organized)


Enzymes
4.   Enzymes are what type of macromolecule?
*My answer: ATP

8.   What function do enzymes perform in chemical reactions?
*My answer: proteins that accelerates/speeds up the rate of chemical reactions

9.   The material that is changed as a result of it’s binding to the enzyme is called…
*My answer: substrate

10.   The location on an enzyme where materials will bind is called…
*My answer: active site

11.   The material that is formed after a chemical reaction is known as…
lock and key


Photosynthesis
12.   What range of visible light is best absorbed by pigments in plants? What range is reflected most?
*My answer: absorbs=red and green light      reflects=blue

13.   What pigments are found in the chloroplast membranes?
*My answer: Chlorophyll
Are there more?

14.   During the photochemical reactions of photosynthesis, the light energy is transferred to what two materials?
*My answer: The photo of photosynthesis; the synthesis of photosynthesis

15.   In order for chlorophyll to absorb light again, how does it replace the lost electron in PS1? PSII?
*My answer: In PS1, light strikes photosystem II, the excited electron is transported to PS1. In PSII, an electrion is pulled away from water to replace these lost electrons from PSII

16.   Explain why water is necessary for plants to perform photosynthesis.
*My answer: It provides electrons to the light dependent reactions

17.   Where does a plant get the atoms of Carbon, Oxygen, and Hydrogen to build sugar (C6H12O6)?
*My answer: Light

18.   During the Calvin Cycle, what is the source of energy to bond the atoms of sugar together?
*My answer: Carbon, Oxygen, Hydrogen.....or is it ATP?


Cell Respiration.
19.   Which step in the process releases the most energy from the molecule of sugar?
*My answer: ETC

20.   Which step in the process splits the molecule of sugar into two three carbon molecules called Pyruvate?
*My answer: Glycolysis

21.   Which step of the process completes the breakdown of all the carbons, hydrogens, and oxygens from the sugar molecule?

22.   What is the role of oxygen in the process of Aerobic cell respiration?
*My answer: Oxygen is needed to function or everything dies. You cannot burn anything without oxygen.

23.   When do cells do fermentation? What are the possible end products of fermentation? What type of cells can do this process?
*My answer: When=process of working without oxygen
What=some cells can perform a partial breakdown of sugar even if oxygen is not available
What type can do this process=bacteria, human muscle cells

[Yggdrasil]

1.  ok
2.  ok
3.  ok
4.  try again
8.  good
9.  good
10.  good
11.  try again
12.  chloroplasts look green.  What does this tell you about the colors reflected/absorbed.
13.  the chlorophylls are the primary pigments present.  Xantophylls and carotenes are also present and these pigments account for the red/yellow colors seen in leaves during the fall.
http://en.wikipedia.org/wiki/Carotenoids
14.  try again
15.  correct
16.  correct
17.  try again.  Think about the dark reactions of photosynthesis (since this is where sugars are built).
18.  see above
19.  correct
20.  correct
21.  where's your attempt?
22.  be more specific.  Maybe compare to the role of water in photosynthesis.
23.  be more specific about what the end product of fermentation are.

[Mon]

the ones I got wrong or did not explain well, what are the answers? I looked forever for like 2 days to pick the best answer/explaination in the way I could understand them. I also looked on this one biology site and some of the answers I could not find in my notes were on there, but some I could not find at all. I was up last night for the 2nd day in a row until 1am trying to find these answers. thats why I finally posted on here what I had trouble with to get the answers. I don't want to take up anymore time finding the wrong answers or ones that are do not answer exactly what the question wants in explaination. its not worth wasting anymore time on these same questions trying to find the answers and trying to understand it to find the answer if I don't understand it. I have quite a bit to still study and I want to take up my time studying my notes rather than finding study guide answers I tried finding for hours in my notes, book, and online. thats why I'm here to ask and get the answers to the ones I got wrong did not explain correctly. I am not good at explaining things at all (reading comprehension problem), so if I can't find the exact, then I have trouble.

[Mon]

I will guess what is in my notes what might be the answer instead of trying to use my reading comprehension online or in the book.  #4, #11, #12, #14, #17, #18, #21, #22, and #23 is what I need answers to. I am going to take a guess based on my notes.



#4 - , there is nothing in my notes that say "Enzymes are what type of macromolecules" and I looked online, and could not find the answer. I thought it was ATP, but it's not.

#11 - Substrate?

#12 - my notes say "plants absorb some wavelengths while reflecting others. Pigments will absorm some wavelengths of light while reflecting others. Plants have a variety of pigments in order to absorb the broadest spectrum of light."

So...should the answer be.. absorb=wavelengths   reflecting=pigments ? I don't understand this.

#14 -
Light Absorption and Calvin Cycle?

#17 - The energy from the electrons

#18 - Carbon and Oxygen come from CO2 in air and hydrogen come from splitting of water.

#21 - Citric Acid Cycle

#22 - I have no idea. The guess I put before was my only guess. My notes does not talk about "the role of oxygen in the aerobic cell respiration.

#23 - I already put my answer, but thats the best I could explain this one.

Whatever is wrong here or not explained correctly, I need the correct answer so I can study the right answers to the questions on my index cards. I am not going to try and guess anymore, because I would be wrong everytime. My reading comprehension is not good.

[Borek]

#4 - , there is nothing in my notes that say "Enzymes are what type of macromolecules" and I looked online, and could not find the answer.

What types of biological macromolecules do you know?

[Mon]

carbohydrates, lipids, proteins and nucleic acids

[Yggdrasil]

4.  Out of your list of macromolecules, to which group do enzymes belong? (hint: see the first sentence of http://en.wikipedia.org/wiki/Enzyme)
11.  Product
12.  Think logically.  You should be able to figure it out without trying to reference a book.
14.  Look at a diagram of the light reactions of photosynthesis (for example, found here http://en.wikipedia.org/wiki/Light_reaction).  What two energy-carrying molecules are produced?
17-18.  You are correct that the carbon and oxygen atoms in the sugars come from carbon dioxide and that the hydrogen atoms in the sugars comes from water.  The ATP produced in the light reaction drives the creation of new carbon-carbon bonds in the Calvin cycle.
21.  Correct
22.  What is the specific function of oxygen in the electron transport chain?
23.  http://en.wikipedia.org/wiki/Fermentation_%28biochemistry%29#Products

[Mon]

#4 - proteins (I know enzymes are proteins, but I was not thinking about one of the 4 macromolecules being the answer...
I have trouble understanding questions sometimes and once I get the answer, I tell myself "I should of knew this". thats apart of my learning disability. If something is not word for word or anything from the question in the sentence in a way I know its right, then I struggle finding the answer.

#12 - absorb=green  reflected most=yellow That's all I can think of. Is it the colors that are the answer? I may have to forget about this question I cannot find an answer.

#14 - Chloroplast stroma and thylakadlumen

For #17 and #18, you put the answers together. Is it the same answer for both or is my answer for #17 "the energy from the electrons" correct?

#17 - energy from the electrons

#18 - carbon and oxygen atoms in the sugars come from carbon dioxide and that the hydrogen atoms in the sugars comes from water.  The ATP produced in the light reaction drives the creation of new carbon-carbon bonds in the Calvin cycle.

#22 - The oxygen we breathe in will be the final electron acceptor forming H2O
(got this from my notes under the ETC area)

#23 - (Note: I am putting this question into 3 parts because there are 3 parts to the question.
 
When do cells do fermentation?
My answer: produced during the reduction of pyruvate to regenerate NAD+ in the absence of oxygen.

What are the possible end products of fermentation?
My answer: I could not find the answer to this one because there is no "end products of fermentation" in any of the sentences for me to find that answer. I am guessing "When yeast ferments, it breaks down the glucose into exactly two molecules of ethanol and two molecules of carbon dioxide."

What type of cells can do this process?
My answer: Lacid acid fermentation and ethanol fermentation (not sure if this is right or not)





One question I forgot to ask that I think I found the answer to in the url you put for #23...

Question is "What is a waste product of any energy transformation?"
My answer: Products produced by fermentation