biology 001-need advice for 2nd exam

Hi everyone, I need advice from y'all thats taken beginning bio. My 2nd exam will emcompass–1)the nature of molecules, 2)the chemical building blocks of life, such as proteins, amino acids,dna 3)cell structure 4)membranes and 5) cell to cell interactions.

All of this material is so overwhelming. My test is Oct. 10.
I have been doing flash cards and I just keep going over my notes. Just what study techniques do you recommend that will get all this in my head??
Also is there a way to remember diffusion, osmotic pressure, hyper and hypotonic solutions, gradients going up or down? Or do you just make charts up and memorize? Also can anyone give me examples of a hypertonic solution and a hypotonic solution?
My first exam I got a B, now I want to hold on to that B or do better.

I more or less just took the test you are about to take… I used flash cards for some of the molecules… we had to know funcitonal groups…
For the hypotonic v. hypertonic solutions. I found it helps to draw it out and think of a cell. Its all relative. Whats out vs. whats in. Hypo meaning less, Hyper meaning more. Less particles- hypotonic, more particles - hypertonic. Osmosis and diffusion also works with drawings. I like to make it feel relevant… again… water into a cell. Ions diffusing in or out of a cell. Drawings with arrows. Visualizing it all in action helps me the most.
Sounds like you are working hard. Putting in the time probably helps the most.
Good luck.

Good News, you have lots of time smile.gif
I tend to prefer more active methods of study than reading notes and reading flash cards.
PM me if you want to go over anything specific - I used to tutor intro to bio.
1) Diffusion & Osmosis
given random molecular motion, everything tends to run downhill - if it can.
for example - a solute will diffuse down its concentration gradient from high to low. downhill.
All sorts of things diffuse given time - a drop of food coloring in a glass of water, an unpleasant odorous emmission from the dog in the corner into the rest of the room - etc.
osmosis is just a special case of diffusion for water - but the twist you have to remember is that it is water running down ITS concentration gradient - consider a membrane dividing 2 areas into an A and B side.
assume the A-side of the membrane is 10% solute (therefore 90% H20), and B-side is 20% solute (therefore 80% water).
in this system, A-side is high [H20], low [solute]. B-side is low [H20], high [solute]
if the membrane is permeable to water, water will move in which direction ?
Down ITS gradent from high to low - that is, from A to B. This is osmosis.
If A-side is outside a cell, and B-side is inside the cell - H20 will move into the cell, causing it to swell and burst.
If A-side is inside, and B-side is outside, H2O will move out of the cell, causing it to shrivel.
If the membrane is permeable to the solute, then the solute will run down ITS gradient.
If you have 2 solutes on each side - they will each independently run down their concentration gradients as much as they can (for now, assume this is true. later you in your studies you might learn that other factors effect the movement of solutes).
I don’t know if you have covered this, do you have to learn facilitated diffusion, active transport, etc, too?
2 ) Hypertonic, Hypotonic.
If it is the terms that give you trouble - think of a hypodermic needle - it shoots UNDER the skin - HYPOtonic solutions are UNDER-salty - that is they have less solute/more water than tonic solutions. HYPERtonic, like HYPERactive, are OVER-salty, more solute/less water than tonic solutions. If you put normal RBC into a HYPOtonic solution - what will happen? What way will water move? What if you put them in HYPERtonic solution?
3 ) Cell Structure
a ) identification
This is where a whiteboard is handy. I used to tell my students when I tutored biology to draw their own cell, speaking the structures aloud as they drew them in - Name them as you draw them. Don’t start from a cell picture - if you must use an aid at first, type a list of the structures and work from the list - alphabetize it in WORD first so you don’t get any hints from seeing things together like mitochondria, cisternae, matrix, inner membrane, etc. Better yet - just put the major organelles on your list and draw the complete structure from memory. Once you have drawn and named everything, and named the function, check it against your book drawing.
B ) function
Here is one place for flashcards, but I use Excel - one column for structure, one column for function.
sort it randomly. print it out and hide one column while working from the other. be sure you can go both ways, structure to function, and function to structure.
c ) terminology and definitions
You might not even see these in this form on an exam, but I had teachers who tested by giving short answer questions and making us write definitions.
Write a list in Word of all terms, concepts, structures, functions, processes, etc. One line per term. Make the list by going over your notes, terms in the text etc. As you write the list, make mental notes of what a definition would be, how you’d explain the process to your very intelligent grandmother, etc. When you have a full list, sort it alphabetically to randomize it. Then format the list so each term will print about 1.5 to 2 inch apart. Print it out.
The next time you study, write out complete definitions and/or descriptions of each term. To me , the important part is to practice WRITING the answer and not just answering mentally because it uses more senses and simulates exam conditions better. If you get stumped, that’s OK - check your notes, formulate an answer, and then write it in. Skip over some for now, and come back to them. It could take you a couple of hours to go through a list like this, but it will be good study time spent. Be sure to check and grade your results. Write complete sentences if you are describing a process. Be sure you write good definitions in your own words - not the glossary entry from the back of the book, but not “Hypertonic: more solute than tonic” either.
4 ) Macromolecules - depends on what level of detail you need - drawing cartoons of lipid structures, peptide bonds, etc. are always good. Are they making you learn all the AA structures or just basic concepts?
5 ) what do you need to know about cell-to-cell interactions? Do you mean cell-to-cell signalling methods? What level of detail? Or do you mean cell-to-cell as in adhesions, gap junctions, etc. ?
6 ) the nature of molecules? I’m not sure what subjects you mean that to cover.
Hope this has given you some ideas of what has worked for me and for my tutees - PM me if you what more help on specific topics - or post here again.

tongue.gif Draw pictures, on paper, or in your head. Most of us are more visual than aural and this helps when you see something written down graphically. Try explaining the concept to someone or yourself, if this can be done successfully, then you know your stuff. And, reread, reread, and redo, and redo. Repeition is good! Aloha.
SurferGene cool.gif

Gosh Lisa you are so good at explaining things! Have you thought about academic medicine?

Thank you all for your responses and I will follow your pearls of wisdom. Lisa, I PM'd you.

The thing that helped me the most during gen bio was answering the questions that were at the back of each chapter. Our book (Cambell) also came with a CD that had a bunch of questions as well. I felt like it really helped me focus in on things. I sold the book but I found the CD last weekend. If your interested, let me know and I'll mail it to you.

The best way that I found to prepare for a bio exam was to get together with a couple of people and answer the questions in the back of the chapter as well as taking old tests that the professor had set out for us.
However, before we answered the question, we looked at each answer and discussed why we though the answer was correct or incorrect.
Good Luck

I'm in the same semester of biology and not looking forward to my second exam, either. But I must agree that a study group makes a huge difference. You can quiz each other, figure things out together, and best of all, explain concepts to each other. Nothing cements a concept in your mind like explaining it to someone else. Hang in there!
A hyperTONic solution has TONS of stuff (solute) in it. (Hyper=lots, just as if you're hyperactive you have lots of energy).
Osmosis is about the flow of water. Think of MOSES–it was the water he moved. Water flows to even out the concentration, so it flows to where there's more solute so the concentration is the same.
Diffusion is the movement of STUFF to equalize concentration. Think of a diffuser on a hair dryer moving your hair around (I know the word means something different here; it's just a mnemonic.)
Thinks move DOWN the concentration gradient. In osmosis water moves from where there's more water than stuff to where there's (relatively) more stuff than water. In diffusion, stuff moves from where there's more stuff to where there's less stuff.
Knock 'em dead, and form a study group! Even if you have to stand up in the front of the room just before class starts and shout to start one (which is what I'm having to do in O-chem).

this is the textbook related site for a human physio text…t/olc/index.htm
but - the topics are similar to those covered in the physiology part of a general biology course - and you may get some additional benefit by reading the corresponding outlines, working through the critical thinking parts (even if you don’t have the text or it is more in depth than you need - always good to think a level deeper), using the flashcards provided, and looking at some of the links provided.
just a thought.

Thank you all for your help and advice. I took the exam, 50 ques. multiple choice. If I bombed it, we do get to drop the lowest test score.
Now I got to do something that just makes me sick. I'm a true blue animal lover, but now I (actually the whole class) has to look up web sites that the prof. selected and write an essay for or against animal research.
I get sick thinking about it, now I have to immerse myself in reading all this material. That's the one thing about med school that I don't want any part of.
I couldn't and wouldn't pith a live frog for a phys class that I took way back in nursing school.
In my state (Wisconsin), the Medical College of Wisconsin is the #1 med school on PETA's list because of what they do to dogs for spinal research and head truama research.
I'm in such a distressed state thinking about this.