Questions

Do you think this new and revised AP Bio test will be harder than the past tests?

I don't think this test will necessarily be more difficult than the AP Bio tests in the past.  It will be more conceptual with less factual recall.  The number of multiple choice and grid-ins is much lower than the previous tests.  This indicates that each question will take more time.  

Can you explain the steps of photosynthesis and cellular respiration?

The following video may help.  013- Photosynthesis and Respiration

Hi can you go over the labs my teacher didnt even do them with us.

I just added the following two videos (video 1) (video 2) which may help.  

Why are non-polar molecules able to diffuse through the membrane?

The polar covalent bond between the hydrogen and oxygen atoms in water creates a polar molecule.  The phospholipid tails have non-polar (uncharged) bonds between the carbon and the hydrogen.  Since the inside of the membrane is non-polar the water "shall not pass".  Water and oil don't mix for the same reason.  Water must move through an aquaporin.

Please go over important things about energy couplings.

Exergonic reactions (like cellular respiration) are coupled with endergonic reactions (like phosphorylation).  This video might help.

How does ATP work?

This video on ATP should help.

Will there be only one correct answer for the grid in questions?

They will accept a range of answers.  

Will these be computer graded or graded by hand?

The multiple choice and grid-in questions will be graded by a computer.  The essays will be graded by humans.  You should write neatly and organize your essay to make it easier on the graders.

What suggestions do you have for the day/night before the AP exam?

I would study the concepts you are struggling with the day before the exam.  You should get a good night's sleep the night before.

How do C4 and CAM plants differ from C3 plants?

Most normal plants are C3 plants because they produce three carbon G3P.  A major problem in plants is photorespiration.  This occurs when oxygen (rather than CO2) combines with RuBP.  The plant receives nothing from this reaction.  CAM plants (like cactus) capture CO2 at night and do photosynthesis during the day.  C4 plants capture CO2 in their mesophyll cells.  Each of these processes require more energy but they allow the plants to survive in hot climates. 

Could you explain the temperature coefficient?

This video on the temperature coefficient should help.

Does the new exam focus more on content and fact recall, or analysis and interpretation?

There will be more focus on analysis and interpretation.

What should we do when we feel over whelmed by the words on the test? 

Don't spend too much time on difficult questions.  Each of the questions is worth the same amount and so you should guess if you have no time left.

Can you clarify how the nephron works in terms of solute concentration and osmosis/ diffusion?

This video on the nervous system should help.

How do operons work?

This video on the operon should help.

Do you have any suggestions as to how to stay calm and focused when you read a question and initially feel as if you have no clue how to answer? (Especially with the long free responses).  

Never skip any of the free response questions.  If the question is very difficult for you it will probably difficult for most students taking the test.  Fight for every point possible and never leave an answer blank.

How can I make sure that I don't run out of time for the free responses?

You should budget about 20 minutes for the long free response and about 6 minutes for the short response.  A wristwatch would be helpful if a clock isn't available.

Can you go over the sliding filament theory like how actin slides across myosin?

I discuss the sliding filament theory in this video on the muscular system.

Please explain Independent Assortment and Punnett squares.

Independent assortment occurs during meiosis.  The chromosomes will line up randomly along the metaphase plate.  For example in a heterozygous plant (Pp)  there will be a 50% chance that the P moves in either direction during meiosis.  The following video might help.

And how do you set up a Punnett Square for blood types?

The following video on blood types should help.  You will need to learn the genotypes of the four blood types to accurately answer these questions.

Could you explain positive and negative feedback loops and explain how they relate other systems in the body?

Negative feedback keeps the level around a set point (like blood glucose).  Positive feedback (like childbirth) moves away from a set point.  The following video on feedback loops should help.  

My question regarding the AP Biology test is regarding heredity. I still can't wrap my head around the concept of "test crosses".

A testcross is used to determine the phenotype of an individual.  For example a purple flower may have one of the following two genotypes (PP or Pp).  A test cross requires you to cross a homozygous individual (pp).  If all of the offspring are purple the genotype  was PP and if half of the offspring are white it was Pp.

Can you please go over the basics of the endocrine system?

The following video on the endocrine system should help.

What is the difference between cyclic and non cyclic photosynthesis?

The Calvin cycle requires more ATP than NADPH.  Therefore some of the electrons from PSI must circle back to PSI.  This will move more protons to the inside of the thylakoid and will therefore create more ATP.

Can you go over the cell parts/what they do and where they are located in?

The following video on the Tour of a Cell should help.

Do we need to memorize the formulas and be able to use and understand them well for the AP Exam?

There is no need to memorize any of the formulas that are on the formula sheet.  You should know how to use all of the formulas.

What are the differences between the lac and trp operons?

The following video on the operon should help.  I discuss both the lac and trp operons.

I would like a quick final review on all the four BIG IDEAS of biology

This introductory video on Biology details the four big ideas.

Will you please explain protein structures and the differences between them/ why the different structures matter (primary secondary etc.)? Thanks! 

The following video on proteins should help.

What do think might be possible frq topics for this year's exam based on statistics from the past few years?

Good question.  You should definitely look at the FRQ's over the last few years to see what they are like.  Here is a link to the old questions.

How do I structure the essays?

All of the questions must be written in essay form (e.g. no bullet points).  Be wary of words like discuss and explain.  These words will require longer answers.

"AaBbCc crossed with AaBbCc" I have no idea about how to do this.

Solve each of the alleles separately.  For example what are the odds of the parents listed above creating the following offspring AABbCc.  Solve each letter individually.  Aa x Aa = AA (1/4)  Bb x Bb = Bb (1/2)  Cc x Cc = Cc (1/2).  Multiply all of the fractions to arrive at the correct answer.  1/16

The difference between biological compounds(proteins, carbohydrates, nucleic acids, lipids, and proteins.

The following video on the Molecules of Life should help.  

For example, lets say an organism has 23 pairs of chromosomes, how many chromosomes does each parent contribute to their offspring?

Each parent gives half of their chromosomes to their offspring.

Na+/K Pump.....what does it really do?

This pumps moves Sodium outside the cell and Potassium inside.  It is used to maintain the potential difference in neurons.

I understand that there are 7 "science practices". What is the best way to review for these science practices?

You can find links to the Practice Videos on the AP Biology page.

What sources of genetic variation exist in bacteria and how do they work?

Transformation Transduction and Conjugation.  The following video should help.

Can you explain the purpose of alternation of generations in plants?

Plants (like animals) alternate between haploid and diploid stages.  The diploid version of a plant is referred to as the sporophyte and the haploid is the gametophyte.

Could you explain entropy, enthalpy, Gibbs free energy, and the equation that connects them?

The following video on Gibbs Free Energy should help.

What's your favorite concept to study in AP Biology?

I enjoy all of the topics but when I study for fun I tend to focus on evolution.

How to design an experiment for an essay question. What are some tips?

The following video should help out.