Tuesday, January 31, 2012

Classical Genetics & Meiosis Test

Today both classes had a test on classical genetics and meiosis.  Tomorrow we will be extracting DNA from strawberries.  This can be a bit messy and the strawberry juice will stain your clothes, so it's best to to wear clothes can get dirty.

Saturday, January 28, 2012

Test Review

On Friday students worked on a review packet for their test on Genetics & Meiosis on Tuesday January 31st.

On Monday we will be starting our next unit on DNA.

Thursday, January 26, 2012

Mutations and Baby Dragons for G period

Today G period learned about various types of mutations as well as created their baby dragons.  Dragons and the questions at the back of the packet are due tomorrow in class.  Please answer the questions on a separate sheet of paper and each person should answer the questions as well as draw his/her own dragon. 

Tomorrow we will recap what we have learned about genetics.

Wednesday, January 25, 2012

Nondisjunction Disorders

Today students did a jigsaw activity to learn about six different types of nondisjunction disorders:
* Down Syndrome
* Edward's Syndrome
* Patau Syndrome
* Klinefelter Syndrome
* Turner Syndrome
* XYY Syndrome

Karyotype of a female with Trisomy 21 from Nature.ca
For homework, complete the vocabulary self evaluation on page 12 of your packet.

Below is a graph for the incidence of Down Syndrome relative to the age of the mother during pregnancy.
Read more about Down Syndrome testing in this New York Times article.

Tuesday, January 24, 2012

Baby Dragons!

C period made baby dragons today in class.  G period will do this activity on Thursday.

C period - answer the questions on the last page of the packet (use a separate sheet of paper to write your answers).  You also need to draw your dragon.  Each person should draw his/her own dragon.

G period - read about TSD in the post below and answer the questions.

Monday, January 23, 2012

Gene Linkage, Sex Chromosomes and Mutations

Today (or tomorrow for G period) we worked on pages 7-9 of the packet.  However, not all species have sex chromosomes.  We talked about sex determination in wasps and tonight for homework, you will learn about the effects that temperature can play on sex determination.

1. Read this article from Davidson.edu on temperature dependent sex determination

2. Answer the following questions:

a. What is the difference between GSD and ESD?

b. What is TSD?

c. Do humans exhibit GSD or ESD?

d. Give two examples of organisms which lack sex chromosomes.

e. What are the two patterns of TSD?

f. Global temperatures have been rising.  What effects could this have on crocodilians and some species of turtles?

Photo Credit Here

Friday, January 20, 2012

Meoisis I

Today we started to learn about Meiosis.


Draw the stages of Meiosis II.  Make sure to label the centrioles in at least one picture.  Draw these pictures at the top of page 7 in your packet.


Thursday, January 19, 2012

Homework for Friday

G period - complete the vocab for pages 1 - 4.

Both classes:

Read and take notes on section 11-4 in your book (starting on page 275) for a reading quiz.  Focus on the key concepts and vocabulary.  To help focus your notes, consider answering the section assessment questions on page 278.   NOTE:  Drawings of the stages of meiosis are NOT required for the reading quiz.  We will be doing an activity in class on Friday where we work with the stages of meiosis and spend time drawing them.

Still struggling? Sing along to the Meiosis Square Dance Video!

Wednesday, January 18, 2012

Variations on Mendel

G period:
Today we completed page 3 in the packet and learned about test crosses and pedigrees.  Spoiler Alert!  If you haven't seen the last Harry Potter movie, this pedigree will ruin the end for you.

It's not very efficient to draw complete portraits for a pedigree.  Instead scientists uses symbols (circles or squares) and shade them in to designate if an individual is affected, unaffected or a carrier.

G Period Homework - Read the post below for information on amniocentesis and chorionic villus sampling.

C period
Today we completed page 5 in the packet and learned about variations on Mendel's principles: incomplete dominance, codominance, pleiotropy and polygenic inheritance.

C period homework:  Read section 11-4 (starting on page 275) and take notes for a reading quiz.  Keep the main points of the reading in mind.  You do not need to draw the stages of meiosis, we will do an activity for this in class.

Tuesday, January 17, 2012

Amniocentesis and Chorionic Villus Sampling

C period - please read over the information below.  Also, in the space at the bottom on page 4 in the packet write out all of the vocabulary you have seen in pages 1-4.

Genetic Testing & Counseling -
We will touch more on this topic later on, but for now you should be aware of two types of tests that can be done during pregnancy to look for genetic disorders.

Chorionic villus sampling (CVS) is the removal of a small piece of tissue (chorionic villi) from the uterus during early pregnancy to screen the baby for genetic defects.

These two tests are amniocentesis and chorionic villus sampling.

Monday, January 16, 2012

Welcome Back to Genetics!

Today we completed pages 1 & 2 of the Mendelian Genetics Packet.  C period complete the following problems for class on Tuesday.  G period complete the problems for Wednesday.

Today we started chapter 11. Below are your homework problems. You do not need to write out the problems, just the answers.

A. For each genotype, indicate whether it is heterozygous (HE) or homozygous (HO)
1. AA ____
2. Bb ____
3. Cc ____
4. Dd ____
5. Ee ____
6. ff ____
7. GG ____
8. HH ____
B. For each of the genotypes below, determine the phenotype.
Purple flowers are dominant to white flowers
9. PP ___________________________
10. Pp ___________________________
11. pp ___________________________

Brown eyes are dominant to blue eyes
12. BB ___________________________
13. Bb ___________________________
14. bb ___________________________

C. For each phenotype, list the genotypes.

(Remember to use the letter of the dominant trait)
Straight hair is dominant to curly.
15. ____________ straight
16. ____________ straight
17. ____________ curly
Pointed heads are dominant to round heads.
18. ____________ pointed
19. ____________ pointed
20. ____________ round
D. Set up the square for each of the crosses listed below.
The trait being studied is round seeds (dominant) and wrinkled seeds (recessive)
21. Rr x rr

22. What percentage of the offspring will be round? ___________

23. Rr x Rr24. What percentage of the offspring will be round? ___________

25. RR x Rr26. What percentage of the offspring will be round? ___________

E. A TT (tall) plant is crossed with a tt (short plant).
What percentage of the offspring will be tall? ___________