HW solutions - Honors and Regular

Hey all,

Here are your solutions. Enjoy!

Regular Class:
p. 315, 3-5, 7-9, 23

3. B
4. C
5. A
7. B
8. C
9. B

23. There are many different types of mutations - gene mutations involve a change in one or more nucleotides in a single gene. Chromosomal mutations are changes in the structure or number of whole chromosomes. Insertion mutations add one or more bases to a sequence. Deletions remove one or more bases from a sequence. Substitution mutations switch one base into another. Inversion mutations reverse the order of a sequence of two or more bases.

p. 269: #2, 4, 5
2. Punnett squares are used to predict and compare the possible outcomes (genotypes) that could result from a cross.

4. Genotype is the specific pair of alleles for a gene that an organism has (Bb or bb); phenotype is the physical trait or characteristic that the organism displays. (Brown hair or blond hair)

5. The cross will be tt x Tt, which results in genotypes Tt, Tt, tt, tt. This means 50% of the plants will be tall.

Honors:

p. 274 - 1, 3

1. During gamete formation, pairs of alleles for different traits segregate (separate) independently from each other. For example, the alleles for seed type (R or r) and seed color (Y or y) in pea plants are independent from each other. This means that in both genotypes RrYY and Rryy, the seed type will be round, while the seed color changes from yellow to green.

3. In incomplete dominance, two alleles combine to produce a single phenotype that is "in between" the dominant and recessive. The example used in class is the snapdragon flower, which is pink for the heterozygous case of Rr. In codominance, each allele is expressed separately in the same organism. For example, cats expressing codominant traits of brown (B) and orange (O) fur might result in fur that is BOTH orange and fur in the genotype BO.

Human Genome Animation

This animation is from the Human Genome Management Information System of the U.S. Department of Energy Office of Science. It shows the details of what the Human Genome project has discovered about the locations of genes on human chromosomes.

http://www.ornl.gov/sci/techresources/Human_Genome/posters/chromosome/karotypehome11.swf

I don't mean to be codominant, but...

Here are the solutions to today's worksheet:

1.
a) If R was the dominant allele, then the genotype Rr would be red, not pink. In this example, Rr represents a third genotype in which the dominant allele is only partly dominant, which makes it pink, a mixture of red and white.

b)
i.100 % pink flowers
ii. 50% white, 50% pink

c) rr x rr or Rr x rr

2.
a)The alleles are A, B, or o - these alleles are used to construct ALL of the other genotypes for blood type.
b)
i. 50% type AB, 50% blood type B (genotype Bo)
ii.50% type A (Ao), 50% type B (Bo)
c) The parents must have been Ao x Bo

3.
b) 4 BbTT, 4 BbTt (these are all Brown fur, Long tail), 4 bbTT, 4 bbTt (these are all black fur, Long tail),
c) 50% have this trait.

Secret word...karyotype. Look it up and be ahead of the game.

Also, click here to read some facts about the human genome.

It's Hip to be a Punnett Square - Honors Classwork Solutions

Hi Everyone,

Great work today in the new classes - I think they will work out well!

Here are the solutions to the handout from class:

Front Page (Level I questions...)

1. Genotypes: 2Gg, 2gg, Phenotypes are 50% green, 50% yellow
2. Genotypes: 2TT, 2Tt, Phenotypes are 100% tall
3. Genotypes: 2Tt, 2tt, Phenotypes are 50% tall, 50% short.
4. Genotypes: 2 Rr, 2rr, Phenotypes are 50% red, 50% white
5. Genotypes are all rr, Phenotypes are 100% white
6. Genotypes are all BB, Phenotypes are 100% black chicken.

Back page problems (Level II)
1. B is brown, b is tan. The cross is BB x Bb.
Genotypes: BB, Bb, BB, Bb, Phenotype is 100% brown mouse.

2. W is white, w is brown. The cross is Bb x Bb.
Genotypes: BB, Bb, Bb, bb, Phenotype is 75% white, and 25% brown.

3. R is red, r is white. The cross is Rr x Rr.
Genotypes: RR, Rr, Rr, rr, Phenotype is 75% red, 25% white.

4. T is tall, t is short. The cross is TT x Tt.
Genotypes: TT, Tt, TT, Tt, Phenotype is 100% tall plant.

5. Period 3 - note the following fact pointed out by someone in the 4th period class: Since it says the white rabbit is heterozygous, this means that WHITE is dominant (not black). If W is white and w is black, then the cross is Ww x ww.

Genotypes: Ww, Ww, ww, ww, Phenotype is 50% white, 50% black.

The secret phrase for today - independent assortment. Extra bonus to those that figure out how this relates to today's lesson....

Midterm Mania - Tuesday Edition

Hi everyone,

After your English and Mathematics midterms, I'm sure you need a break before you get back to the books and study for the rest of your exams.

Check out this great site on how DNA is used to solve crimes, improve how food is grown, and identify how different diseases are related to each other. The site is sponsored by the Koshland Science Museum in Washington D.C.

You can click HERE to access a single file with all of the study guides together. Enjoy.

Also, today's secret word is somewhere on the blog. Find it.

Midterm Review 4 - Solutions

These solutions are for today's review on cellular respiration, photosynthesis, mitosis, DNA and feedback.

Warm-up Questions:

a) guard cell (be aware - the stomate/stoma is just a space within the leaf, and does not actively control anything.)

b) green (The colors we see are those colors that are NOT absorbed.)

c) mitochondrion

d) chloroplast

e) 6CO2 + 6H2O ---light---> C6H12O6 + 6O2

f) C6H12O6 + 6O2 -------> 6CO2 + 6H2O + ATP (usable energy)

g) oxygen

h) cellular respiration (fermentation is faster, but it uses up glucose much more quickly.)

i) TACCGATACC

j) CCAAGGUU

k) A goes with T, C goes with G

l) gene, DNA, chromosome, cell

m) 24 (Daughter cells after mitosis will be the same as the original cell.)

n) metaphase

o) interphase

p) positive feedback

q) dynamic equilibrium

r) independent variable - type of fruit

MC Questions

1. (2)

2. (3)

3. (2)

4. (3)

5. (4)

6. (Sorry about the strange formatting and skipping the diagram)

a) (1)

b) (3)

9. (2)

10. Some organisms change solar energy into chemical energy using photosynthesis. This process takes place in chloroplasts.

11. (Remember that cells after division are identical to each other and to the original cell.)

12.

a) oxygen gas (Cell A is a plant cell based on the diagram. Substance X is sent out as a waste product from cell A, and is taken in by cell B, therefore it must be oxygen gas.)

b)cellular respiration

c) mitochondria (Both plant and animal cells have mitochondria, because they must both perform cellular respiration.)

68. (There are many possible correct answers that refer to the relationship between the independent and dependent variable.) Examples:

• Plants grown at higher temperatures will grow tall more quickly
• If the temperature increases, the rate that a plant will grow will decrease.

(Do NOT explain in a hypothesis - merely state a relationship between the variables in the experiment. In short, never use the word '"because" in a hypothesis.)

69. Temperature and the height of the plant, for example. (This should match the quantities being measured in your hypothesis.)

70. (In questions like this, remember the things we have discussed that make for an experiment with reliable results, such as using multiple trials, and ensuring only one independent variable.)

Examples of correct answers:

Use multiple plants at each temperature, use more temperature values, conduct repeated trials of lily plants, increase the sample size.

Final Question:

Errors in the investigation include...

• multiple independent variables (females given more food than the males, males and females receive different amounts of ibuprofen.)
• no control group (mice given regular amounts of food and water, but no ibuprofen.)

And, to continue the tradition of sharing cool stuff with you at the end of a review session, check out the video below to see some of the most frightening insects I've seen in a while...



Oh yeah, the bonus word for Monday, January 25th is evolution. Send me an email or text with the word before 10 PM to be eligible for your prize tomorrow.

Midterm Review Sheets 1,2 and 3 - Solutions!

Review 1 - Scientific Method, Unity & Diversity, Biochemistry

Quick Review:
a) energy
b) the quantity in an experiment that is measured, observed or tested
c1) three fatty acids attached to a glycerol
c2) the process by which molecules are bonded together by the loss of a water molecule
d) calculations are not necessary for a good experiment - the others are essential!
e) speed
them up/lower the activation energy
f) contains more than one element
g1) because it does not contain BOTH carbon and hydrogen
g2) CO2 + H2O --(light)--> C6H12O6 + O2
h) CO2, water and ATP
i) simple sugars
j) it produces its own food
k) kingdom animalia
l) because it serves to warm up the body and return its temperature to normal levels.
m) grasshopper, hawk, mushroom, butterfly - these organisms all obtain food from the environment
n) H (hydrogen), S (Sulphur), and O (oxygen)
o) acidic - if pH is less than 7, solutions are acidic. 7 is neutral, above 7 is basic.

MC Questions:
1. (2)
2. (4)
3. (1)
4. (3)
5. (2) - the handout used in the regular class has a different question with answer (3) of organelle
6. (1)
7. (3)
8. (4)

9. Grasses and shrubs are producers because they make their own food. They do not eat other organisms, so the arrows always point away.

10.
Photosynthesis: Water and carbon dioxide are combined using the energy of light to form glucose and oxygen gas.
Respiration: Glucose and Oxygen are converted through respiration into ATP, with waste products of water and carbon dioxide.

Cellular respiration is essential because it converts the energy in glucose into a form (ATP) that can be used by cells to perform life processes.

Photosynthesis is essential because it allows the Euglena to produce glucose on its own using light energy, allowing it to survive when food is not available.

12.
The experiment lacks a control group that does not use the plant hormone auxin. The student therefore can't compare to determine whether the hormone helps or not.

Brine Shrimp experiment answers:
THe key to questions like these is to make sure you answer ALL parts of the question. Here are suggested answers to each part as given from the actual Regents grading rubric:

• state how many containers to use in the experiment, and describe what would be
added to each container in addition to the eggs [1]

Three containers, each with a different salt concentration (2%, 4%, and 6%), should be used.
— four containers, one with water, the other three with different salt concentrations (2%, 4%, and 6%)
— four containers, a control and the others with 2%, 4%, and 6% salt solution

• state two factors that must be kept constant in all the containers [1]

— temperature of the water

— number of eggs per container

— salt-water level or volume

— size of container

— amount of time

• state what data must be collected during this experiment [1]

— how many eggs hatch in each salt concentration

• state one way to organize the data so that they will be easy to analyze [1]

— arrange the data in a data table or a spreadsheet

— graph the data

• describe a result that would indicate the best salt solution for hatching brine shrimp

eggs [1]

— The solution that has the most eggs hatch is the best one to use.

Review 2 - Cell Structures, Transport, and Diffusion

Warm up questions:

a) ATP

b) chloroplast

c) nuclear envelope or nuclear membrane

d) nucleolus, which is inside the nucleus

e) to receive vesicles of proteins from the ER, and modify or package them to go elsewhere in the cell

f) rough ER contains ribosomes for protein synthesis

g) energy

h) two layers of phospholipids, the polar or hydrophilic "heads" on the outside of the layer, and the non-polar or hydrophobic "tails" pointed into the layer.

i) the concentration of solute in solution A is greater than the solute concentration of solution B

j) it will expand or burst, since water flows into the cell

k) movement from low concentration to high concentration

l) osmosis is diffusion of water across a membrane

Cell parts:

1. vacuole

2. cytoplasm

3. nucleus (and more specifically, the nucleolus)

4. endoplasmic reticulum, or ER

5. mitochondrion

6. cell membrane

Organelle Chart:

nucleus - contains genetic material and separates it from the cytoplasm, also considered the control center. It is in both plant and animal cells.

ribosome - synthesizes proteins using information in messenger RNA. In both plant and animal cells (along with prokaryotes)

vacuole - stores food and water. In both animal and plant cells, though in plant cells, the central vacuole is very large.

cell membrane - controls transport into/out of cell, in BOTH plant and animal cells.

cytoplasm - fluid that dissolves materials in the cell and helps to give the cell shape. In both plant and animal cells.

mitochondria - convert energy in food (glucose) into ATP, which is a form of energy that cells can use to power life processes

endoplasmic reticulum - location of protein and lipid synthesis in the cell, as well as a transport organelle for these molecules to the rest of the cell. The rough ER contains ribosomes, while the smooth ER produces lipids and does not have ribosomes. In both plant and animal cells

cell wall - a rigid structure made of starch (cellulose) that lets water and gases through. Only contained in plant cells

chloroplast - carries out the process of photosynthesis, in plant cells only.

MC Question Answers:

1. (1)

2. (2)

3. (3)

4. (4)

5. (4) - the cell membrane is where molecules enter the organism through diffusion, which is what happens in the lungs with oxygen and the bloodstream.

6. (1) - you can answer this either by recognizing the structure of a chloroplast, OR by recognizing the reaction described as photosynthesis.

7. Your diagram should have the following to get full credit on this question:

• I (starch indicator) both inside and outside the bag
• G (glucose) both inside and outside the bag
• S only on the inside of the bag (starch is too large to pass through the membrane.

The second part of this question asks for what will be observed when starch indicator is in contact with starch - you may remember from class that any indicator changes color when in contact with the chemical it detects. Specifically, iodine turns a blue-black color when in contact with starch. Either answer (color change, or the appearance of a blue-black color) would be acceptable.

10. You should be able to recognize that cell X is an animal cell and cell Y is a plant cell.

In both cases, each structure is given by:

A - cell membrane

B - nucleus

C - mitochondrion

11.

nucleus - coordinates all cell activities, contains genetic material

cell membrane - controls transport into/out of the cell

mitochondrion - converts food into usable energy through cellular respiration

12. Since cell Y is a plant cell, only photosynthesis occurs in cell Y.

Back Page:

a) If salt is added to the cells, water will flow from inside the cell to outside where the water concentration is less. As a result, the cell will shrink, as shown in View B. The correct answer is salt.

b) Water diffuses out of the cells to change their shape. A common mistake is to say that the cell changes shape because the salt diffuses into the cell - this is not true.

c) You just need to draw a picture that shows MORE cells are visible under low power. Under low power, the magnification is lower, so more cells can be seen.

Saturday School Solutions:

1) 4

2) 1

3) 3

4) 2

5) 3

15) 3

30) 4 - this question is at the bottom of the first page, with the numbers cut off.

31) 2

32) 3

34) 3

35) 4

39) 1

40) 2

41) 4

42) 1 - starch molecules are composed of simple sugars bonded together. The diagram shows the starch molecule being broken apart.

43) 3 - enzymes always work best at a specific temperature and pH. When the temperature rises above a maximum temperature, or outside of a specific pH range, the enzyme can change shape and stop working. When the temperature decreases below its optimal temperature, an enzyme doesn't work as well, and the chemical reaction it controls slows down.

47 - 48:

49. 35 degrees - the graph has its maximum at this temperature. (You need the temperature AND a reason for full credit!)

50. Catalase is an enzyme, which is also a protein.

72. The control group is the group of maple seeds with a pH of 5.6, since this is the pH of normal rain. The scientist wants to compare the more acidic water samples with normal rain.

73. The dependent variable is the number of seeds that had germinated (sprouted)

74. If fewer maple seeds sprouted with the lower pH water, this would explain why there would be fewer young maple trees in regions with acid rain.

59. There are many possible correct answers to this, but a few answers that would NOT receive credit. Some examples:

• digestion is part of nutrition, so it would not be accepted.
• reproduction is not accepted because it is not involved in homeostasis
• giving a correct process, but NOT an explanation would not earn any points.

Correct answers:

Transport moves materials in and throughout an organism, allowing it to keep living functions working.

Excretion removes wastes from the organism. This keeps chemical levels within normal levels.

66. Unfortunately, the correct answer was covered up on the handout (sorry!) by Question 75 - the correct (and hidden) answer is "separate components of chemical mixtures"

67. Choice 2 - the starch can't diffuse out of the tube since starch molecules are too big, but the starch indicator CAN diffuse into the bag. This means the starch indicator will turn blue when it diffuses into the tubing.

68. This demonstrates the process of diffusion.

Whew!

That was a lot of work. For some fun, wrap your head around this slug that is photosynthetic:

Don't forget to visit the quizlet site and review your vocabulary! The links are to the right.

I have also added a link to a Living Environment site that is filled with Regents questions for practice.