In this lesson our instructor talks about sex-linked traits and pedigree analysis. First she talks about sex-linked traits, X-inactivation and barr bodies. Then she discusses pedigrees, autosomal dominant inheritance, autosomal recessive inheritance, and X-linked recessive inheritance. Four complete example videos round up this lesson.
have 23 pairs of autosomes and one pair of sex chromosomes. Males
are XY and females are XX. Genes that are located on the sex
chromosomes are called sex-linked genes.
In females, one copy of the X-chromosome
is inactivated in each cell. The inactivated copy of the X
chromosome is called a Barr body.
A pedigree is a diagram of a family tree
that indicates the phenotype of individuals for a particular trait.
Pedigree analysis can help to determine the inheritance pattern of a
trait or genetic disorder.
Pedigrees for traits with an autosomal
dominant inheritance pattern show an approximately equal number of
affected males and females. Autosomal dominant traits do not skip
a trait is inherited in an autosomal recessive pattern, males and
females are approximately equally affected. The trait may skip a
are more frequently affected if a disorder has an X-linked
recessive inheritance pattern. Females may be carriers and these
disorders can skip a generation.
Sex-Linked Traits and Pedigree Analysis
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
The book and CD package include two full length practice exams that are presented with all questions answered and explained. The author also presents detailed reviews of all test topics and includes multiple-choice and free-response questions with answers at the end of each topic's chapter.
This book includes a review of the AP Biology exam format and scoring, proven strategies for answering multiple-choice questions, and hints for tackling the essay questions. The practice tests include answers and explanations and there is also proven test-taking strategies for both the multiple choice and essay parts.