True-False Quiz 5 - Genetics:
 
True / False
Statement
 

A karyotype is a picture of cells undergoing crossing over.
 

A normal human somatic cell contains 23 pairs of chromosomes.
 

The production of egg cells by meiosis is called "oogenesis".
 

Chromosomes are paired up in a karyotype according to colour.
 

The absence of one of a pair of chromosomes on a karyotype is referred to as a "monosomy".
 
True / False
Statement
 

Down Syndrome occurs when an extra X chromosome is present.
 

XY represents the sex chromosomes for a normal female.
 

XXY represents a female with Turner's Syndrome.
 

XO represents a female who is usually short and infertile.
 

Assume H = normal blood and h = hemophilia. An individual with XhXH would be a female suffering from hemophilia.
 
True / False
Statement
 

Assume H = normal blood and h = hemophilia. An individual with XhY would be a male suffering from hemophilia.
 

Genes located on the X chromosome are said to be "sex linked".
 

Most sex linked disorders are passed on to daughters.
 

Only men can be carriers of sex linked disorders.
 

If a sex linked disorder is caused by a dominant gene (D), an individual with genotype XDXd will suffer from the disorder.
 
True / False
Statement
 

The sperm cell ultimately determines the sex of a baby because a sperm cell can carry either an X or a Y chromosome.
 

Sperm cells carrying the X chromosome can be separated in the lab from those carrying the Y chromosome because the Y chromosome is smaller making these sperm lighter.
 

In Mendelian genetics, a capital letter represents a dominant trait, ie. "t".
 

The genotype "Tt" is called "homozygous".
 

In the cross: Tt x Tt (where T = tall, t = dwarf), 75% of the offspring are tall.