1. Basics of Genetics
Part 1

2. Introduction Cells come from existing cells – the cell theory
“Like produces like” – dogs produce pups not kittens
But how???????
Heredity- transmission of traits from one generation to the next
Genetics- the science of heredity usually dealing with the molecular basis

3. DNA Genetics: Study of heredity and DNA
Discovered in the late 1800’s (not known as genetic material yet.) (Proteins)
Limited by technology
Located inside nucleus of cell (also in mitochondria, chloroplast, virus and bacteria).
Purpose of DNA is to code for proteins.
Made up of a phosphate, sugar and nucleotide bases.
Arranged in a double helix (twisted ladder).
Watson and Crick (1953)

4. II. DNA A. Structure Nucleotide
Phosphate group + Sugar + Nitrogen base

5. DNA cont. Four nucleotide bases:
Adenine A always pairs w/ T
Thymine
Guanine G always pairs w/ C
Cytosine Complimentary base pairs
2-3 billion base pairs in DNA
Chargraff’s ratio: #A = #T and #G = #C

6. Diagram of DNA

7. RNA Acts as an intermediary between DNA and protein.
Common in cytoplasm of the cell.
Transfers code from DNA to ribosome (where protein is made).
Made of phosphate, sugar and nucleotide bases.
Single stranded.

8. RNA cont. Four nucleotide bases: Adenine A always pairs w/ U
Uracil (replaces thymine)
Guanine G always pairs w/ C
Cytosine

9. RNA cont. Three types of RNA
mRNA- (messenger) carries information from DNA to ribosome
tRNA- (transfer) carries amino acids to ribosome
rRNA- (ribosomal) assembles amino acids to make protein

10. 3 Important Processes Replication: DNA making copies of itself
Transcription: DNA makes RNA
Translation: Protein synthesis (making proteins)

11. Comparing DNA and RNA DNA RNA Deoxyribose (sugar) Double stranded
Thymine
Located in nucleus
RNA
Ribose (sugar)
Single stranded
Uracil
Found in cytoplasm

16. After amino acids have bonded, the tRNA leaves.
Continues until STOP codon
Protein synthesis is done
New protein is released

18. Sickle Cell Anemia A genetic disease passed down through families.
Abnormal protein (hemoglobin – carries oxygen) causes red blood cells to be sickle shaped rather than round.
Results in blood clots and fatigue from lack of oxygen passing through blood stream.

19. Sickle Cell Anemia

20. DNA code CAT ______________ _______________
mRNA codon _____________ GUU _______________
tRNA anticodon _____________ ______________ _______________
Amino acid ____________ ______________ methionine

21. DNA code TGA ______________ _______________
mRNA codon _____________ UCU _______________
tRNA anticodon _____________ ______________ _______________
Amino acid ____________ ______________ tryptophan