Chapters 14 & 15 Test Hints

Read the Cliffs Notes Book chapter on Heredity.
Do the Quiz- know how to get all the answers (don’t memorize the answers but learn how to do them all so if you see similar problems on the test you’ll be able to figure them out.)
Know the Free Response answer in the Cliffs Note Book since it will be the one I will give you. You might want to supplement the answer they give you by doing a little extra reading in the book to flesh it out a little better.

Go over my PowerPoint Lectures and notes.

Be sure you can do all the genetics problems I gave you (review your worksheets and the answers)
Know what a test cross is and why it is used.

Know Mendel’s Law of Segregation and how the Chromosomal Theory of Inheritance supports it.

Know Mendel’s Law of Independent Assortment and how the Chromosomal Theory of Inheritance supports it.

Know what Incomplete Dominance is and how to do a problem with it.

Know what Codominance is and how to do a problem with it. The problem will most probably deal with blood types. Understand blood types VERY well. Know the ABO blood typing system.

Know what epistasis is and how to do a problem with it.

Understand the difference between pleiotropy and polygenic inheritance. I didn’t cover polygenic inheritance in class so read about it in the book page 250-251. Figure 14.12 is a great illustration of the idea; check it out. There will definitely be a basic question on polygenic inheritance, so know the basic idea.

I did not have time to cover all the following disorders. You simply need to know what the disease is (basic symptoms) and how it is inherited (autosomal recessive, autosomal dominant, or sex-linked recessive).

Autosomal Recessive Disorders
Cystic fibrosis (page 254)
Phenylketonuria (PKU) (page 258)
Tay-Sachs Disease (page 254)
Sickle Cell Anemia (page 255)

Autosomal Dominant Disorders
Huntington’s Disease (page 255)

Sex-Linked Recessive Disorders
Hemophilia (page 270)
Red-Green Colorblindness (page 269-270)

Know what gene linkage is and how to do basic problems with genes that are linked on the same chromosome. Know how to tell how genes are mapped on a chromosome by their frequency of recombination.

Be able to do problems using sex linked traits. Try a few practice problems at this site if you need to practice these kinds of problems. Remember that sex linked traits are "x" linked traits, i.e. they are found on the "x" chromosome.

Know what a barr body is.

Know what non-disjunction is and the meaning of the terms: aneuploidy, trisomic, monosomic, polyploidy.

Know the various alterations of chromosome structure that can occur: deletions, duplications, inversions, reciprocal translocations.

Know the cause of Down’s Syndrome, Turner’s Syndrome, and Klinefelter’s Syndrome.

Understand the phenomenon of genomic imprinting.
Fragile X syndrome is the most common form of mental retardation with a genetic basis. The incidence of Fragile X syndrome (see bottom of page 274) is explained using the idea of genomic imprinting. The syndrome is more common if the abnormal X chromosome is inherited from the mother. Since males get their X chromosome from their mother they tend to exhibit this disorder more frequently than females.

I forgot to mention this in class: Know that mitochondrial DNA is only inherited from the mother.

I didn’t have time to cover this in class: be able to read and understand a pedigree analysis (see page 253). Try a practice problem at this site if you need to know how to do these kinds of problems. The problems you will get on the test will be straightforward and may not require studying this but a quick look at how it is done may give you a little more confidence.