HEREDITY AND DNATHEORY OF HEREDITY

BY: SARAH SHARIF

EIMAN RANA MYP-V (ARMSTRONG)

INTRODUCTION:Gregor Johann Mendel:• An Austro-German Monk• Botanist/Scientist• Mathematician• Discovered basic principles of

heredity • Experimented Pea plants for the

study of genetics• “Father of Genetics”

GENETICS:• The Study of Heredity. • Study of how heritable traits are transmitted

from parents to offspring.• Two hundred years ago, biologists did not

recognize that there was such a thing as 'heredity'. By the 1830s, however, insights from medicine and agriculture had indicated that something is passed from generation to generation, creating the context for the brilliant advances of Mendel.

THE BLENDING THEORY OF INHERITANCE

• 19th century; biologists held to the idea• Prior to the discovery of genetics• Not a formalized scientific theory (a kind of hypothesis)• States that: inheritance of traits from two parents produces

offspring with characteristics that are intermediate between those of the parents.• Plants in Mendel’s garden didn’t obey blending theory (he

questioned)• Experimented 30,000 pea plants

HEREDITY THEORY:• Many physical traits caused by DNA passed from one generation to the

next.• Some traits are dominant while some recessive• A pure-breed pea plant line is a homozygote - 2 identical copies of the

same allele. • A cross-breed pea plant is a heterozygote –2 different alleles.During experiment, considered :• Flower colour is purple or white• Seed color is yellow or green• Flower position and stem length. • Seed shape is round or wrinkled

• Pod colour is yellow or green and pod shape.• Cross-breed hybrids and found that

traits were inherited independently of each other

INTERESTING FACTS:• He worked as a gardener and studied beekeeping in his childhood.• Despite attempting twice, he failed to become a certified teacher• Green eye color is the rarest eye colour.• Genetic similarity. People share 7% of genetic material with the

E.coli bacteria, 21% with worms, 90% with mice and 98% with chimpanzees.

• The full stop at the end of a sentence is the size of one thousand cell nuclei.

THANK

YOU!