CH 14 THE HUMAN

GENOME

14-1. HUMAN HEREDITY

1. HUMAN CHROMOSOMES

Twin brothers in India

5 MIN ACTIVITY Complete the “Inquiry Activity” on page 340

Karyotype- A picture of chromosomes arranged in this way is known

Biologist use a Karyotype to find defects in the chromosome number

Sex Chromosomes- c’somes that determine the sex (gender) of an organism

Humans females have:have two copies of an X chromosome (XX)

Human males have: Males have one X chromosome and one Y chromosome (XY)

Life cannot exist w/o the X c’some Life can exist w/o the Y c’some

Human Female Karyotype (XX)

Human Male Karyotype (XY)

Autosomes- Any chromosomes that does not determine sex

Humans have 22 pairs or 44 autosomes and 1pair or 2 sex c’somes

A human male is 46, XY A human female is 46, XX There is a 50:50 chance of a

person being male of female

2. HUMAN TRAITS

Pedigree-a diagram that shows the occurrence and appearance or phenotypes of a particular gene or organism and its ancestors from one generation to the next

Pg. 343 Problem Solving complete

Genes & the Environment- many human traits are controlled by many genes or polygenic HeightBody shapeSkin color, etc

DISCUSS W/ PARTNER

5 ways your environment can determine how you features (how you look)

Environment plays a role also

Temp Diet Geography Smoke , alcohol

abuse, drug abuse, etc.

3. HUMAN GENES

All humans and many other primates can be typed for the ABO blood group

There are four phenotypes: A, B, AB, and O There are two antigens and two antibodies

that are mostly responsible for the ABO types

MULTIPLE ALLELES FOR THE ABO BLOOD TYPES

There are two types of inherited disorders in humans; recessive & dominant

Recessive DisordersMost human disorders are recessiveCystic Fibrosis is common in the U.S. Excessive mucus secretion clogs the lungsFew black people have the disease (1/17,000)

More white people have the disease (1/1,800)

Dominant DisordersOnly copy of allele needs to present for the

disordered to have the disease