ppt intro to genetics m.6

EIS Teaching – Learning Strategies / Procedures

Biology Secondary 6, duration 60 min.

Teacher: Mr.Wichai Likitponrak

Look at this Picture!

What is genetics?

The scientific study of heredity

Gregor Mendel

Born in 1822 in Czechoslovakia.

Became a monk at a monastery in 1843.

Taught biology and had interests in statistics.

Also studied at the University of Vienna

Mendel’s Peas

Easy to grow.

Easily identifiable traits

Can work with large numbers of samples

Homozygous = when an organism possesses two

identical alleles. ex.

YY or yy

Heterozygous = when an organism possesses

different alleles. ex.

Yy

Phenotype vs genotype

Genotype

The genetic makeup

Symbolized with

letters

Tt or TT

Phenotype

Physical

appearance of the

organism

Expression of the

trait

Short, tall, yellow,

smooth, etc.

Gene and DNA

Genes are made from a

long molecule called DNA, which is

copied and inherited across generations.

DNA is made of simple units that line up

in a particular order within this long

molecule. The order of these units carries

genetic information, similar to how the

order of letters on a page carries

information.

Chromosome Structure

A chromosome is a structure

of DNA, protein, and RNA found in cells. It

is a single piece of coiled DNA containing

many genes, regulatory elements and

other nucleotide sequences. Chromosomes

also contain DNA-bound proteins, which

serve to package the DNA and control its

functions. Chromosomal DNA encodes

most or all of an organism's genetic

information.

Chromosome number

All cells of an

organism contain a

specific number of

chromosomes.

Most cells are

diploid (2n) meaning

they have two

copies of each

chromosome

Karyotype of Human

Gene Maps

First developed by Sturtevant in 1911.

The farther apart two genes are, the more likely they will be separated in meiosis.

Gene and Allele

•The information within a particular gene is

not always exactly the same between one

organism and another, so different copies of a

gene do not always give exactly the same

instructions. Each unique form of a single

gene is called an allele.

• If one allele overrides the instructions from

another, it is called the dominant allele, and

the allele that is overridden is called

the recessive allele.

Review by this VDO!!!

http://www.youtube.com/watch?v=UB6Upeo-HDE

Assignment:

Worksheet

Pages 5-7

1.1, 1.2 and 1.3

Sent me back

in this class !!!