DNA Deoxyribose Nucleic Acid
-
Upload
phyllis-weeks -
Category
Documents
-
view
23 -
download
1
description
Transcript of DNA Deoxyribose Nucleic Acid
![Page 1: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/1.jpg)
DNADeoxyribose Nucleic Acid
![Page 2: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/2.jpg)
DNA• DNA is a double helix.
• A bonds to T: C bonds to G
• In man, the DNA molecule , if fully extended, would have a total length of 1.7 metres. If you unwrap all the DNA you have in all your cells, you could reach the moon ...6000 times!
![Page 3: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/3.jpg)
DNA
•DNA STRUCTURE•DNA REPLICATION
![Page 4: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/4.jpg)
Components of DNA• NUCLEOTIDE
– Phosphate group-phosphodiester bond– 5-Carbon sugar-deoxyribose– nucleic acid (1 of the nucleic acids)
• Guanine-Purine• Cytosine-Pyrimidines • Adenine-Purine• Thymine-Pyrimidines • Held by hydrogen bonds• One end of chain with free 5’ phosphate group
• Other end of chain with free 3’ hydroxyl group
• Adenine, thymine form two bonds• Guanine, cytosine form three bonds
![Page 5: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/5.jpg)
COMPONENTS
![Page 6: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/6.jpg)
![Page 7: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/7.jpg)
![Page 8: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/8.jpg)
![Page 9: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/9.jpg)
![Page 10: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/10.jpg)
DNA Replication• DNA is opened by enzymes (unzips) helicase
• Complementary nucleotides bond with the old strands-
• 2 strands created: ½ is the old strand; ½ is the new strand.
![Page 11: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/11.jpg)
DNA REPLICATION• TAKES PLACE IN THE NUCLEUS
• END PRODUCT IS TWO IDENTICAL STRANDS
• DURING CELL DIVISION- ONE STRAND
• FOR EACH CELL
• Replication occurs only in 5’(P) to 3’(OH) direction(DNA IS READ 3’ to 5’)
• a. Replication of leading strand, 3' to 5' strand
• 1. New strand grows from 5' to 3’end• 2. Elongates towards replication fork
![Page 12: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/12.jpg)
![Page 13: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/13.jpg)
REPLICATION
ENZYMESHelicaseDNA polymeraseTopoisomeraseRNA primerligase
![Page 14: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/14.jpg)
![Page 15: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/15.jpg)
QuickTime™ and ampeg4 decompressor
are needed to see this picture.
![Page 16: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/16.jpg)
QuickTime™ and ampeg4 decompressor
are needed to see this picture.
![Page 17: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/17.jpg)
![Page 18: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/18.jpg)
From Genotype to PhenotypeFrom Genotype to Phenotype
• Protein synthesis--converting the genetic code (in DNA) into proteins that the body uses
• 3 Steps involved– Transcription– RNA splicing– Translation
• Protein synthesis--converting the genetic code (in DNA) into proteins that the body uses
• 3 Steps involved– Transcription– RNA splicing– Translation
![Page 19: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/19.jpg)
QuickTime™ and ampeg4 decompressor
are needed to see this picture.
![Page 20: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/20.jpg)
![Page 21: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/21.jpg)
![Page 22: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/22.jpg)
![Page 23: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/23.jpg)
![Page 24: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/24.jpg)
![Page 25: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/25.jpg)
DNA----RNA
• DNA• DOUBLE
STRANDED• DEOXYRIBOSE• NUCLEIC BASES
– THYMINE
– GUANINE
– ADENINE
– CYTOSINE
• RNA• SINGLE STRANDED• RIBOSE• NUCLEIC BASES
– URACIL
– GUANINE
– ADENINE
– CYTOSINE
![Page 26: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/26.jpg)
RNA Differences from DNA
– Single stranded (vs. Double stranded DNA)– Contains uracil in place of thymine– Ribose sugar (instead of deoxyribose)
4 Types of RNA preMRNA---transcribes the message from the
DNA(rough blueprint)– mRNA (messenger RNA)-carries message to to
ribosome(final blueprint) – rRNA (ribosomal RNA)--makes up the
ribosome(forman that assembles parts of protein in a specific order)
– tRNA(transfer RNA)--carries amino acids to ribosomes
![Page 27: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/27.jpg)
tRNA• Anticodon of MRNA• Wobble to take in all
possible aa combinations of 3 nitrogen bases
• Carries specific aa on 3’ on of strand
![Page 28: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/28.jpg)
![Page 29: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/29.jpg)
![Page 30: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/30.jpg)
DNA TRANSCRIPTIONDNA- GIVES CODE TO preRNA
or hnRNA
![Page 31: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/31.jpg)
PROCESSING
![Page 32: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/32.jpg)
![Page 33: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/33.jpg)
![Page 34: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/34.jpg)
![Page 35: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/35.jpg)
QuickTime™ and ampeg4 decompressor
are needed to see this picture.
![Page 36: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/36.jpg)
QuickTime™ and ampeg4 decompressor
are needed to see this picture.
![Page 37: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/37.jpg)
RIBOSOME STRUCTURE
A site - attracts Trna
P site - forms peptide bonds between aa of protein
E site - where Trns leave ribosome and aa chain elongates
5’ end with initiator sequence attaches to small subunit
Large subunit goes over small at the A site.
Attracts 1st Trna with aa Met
![Page 38: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/38.jpg)
DNA TRANSLATIONtRNA translates mRNA into proteins
![Page 39: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/39.jpg)
![Page 40: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/40.jpg)
SUMMARY
![Page 41: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/41.jpg)
Comparison of DNA and RNA• RNA is single stranded
• RNA has uracil instead of thymine
• A-U
• DNA is double stranded
• DNA has thymine instead of uracil
• A-T
![Page 42: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/42.jpg)
Understanding DNA
• Inheritance/ Genetic Counseling• Cell function/protein synthesis• Embryonic development/gene regulation
• Evolution/ phylogenetic relationships
• Medicine/genetic diseases• Genetic engineering/ recombinant DNA
![Page 43: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/43.jpg)
Changes in Chromosomes
• Mutation--a change in the sequence of DNA nucleotides (nitrogen bases)– Causes a change in the protein formed– Causes a change in organisms’ phenotype (trait)
• Effects of mutations?– Some have little or no effect– A few are beneficial– Most are harmful or lethal (fatal)
![Page 44: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/44.jpg)
Chromosomal Mutations• Deletion mutation--piece of chromosome breaks off and is lost; the new DNA strands are also missing a piece
• Duplication--piece of chromosome breaks off and is inserted on homologous chromosome
• Translocation--piece of chromosome breaks off and attaches to a different, non-homologous chromosome
• Inversion--piece of chromosome breaks off, turns around and reattaches in opposite direction
![Page 45: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/45.jpg)
Mutations Illustrated
![Page 46: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/46.jpg)
Gene mutations
• Frameshift mutation--deletion or addition of single (or few) nucleotides alters the amino acid sequence of the protein
• Point (Substitution) mutation--wrong base is added in a position--new DNA chains will show the change
![Page 47: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/47.jpg)
Point Mutations
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
![Page 48: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/48.jpg)
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
![Page 49: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/49.jpg)
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
![Page 50: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/50.jpg)
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
![Page 51: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/51.jpg)
MUTATIONS
![Page 52: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/52.jpg)
![Page 53: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/53.jpg)
![Page 54: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/54.jpg)
![Page 55: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/55.jpg)
![Page 56: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/56.jpg)
![Page 57: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/57.jpg)
Frameshift Mutations
Expansions are responsible for many genetic diseases:
• Muscular Dystrophy (CTG repeats)
• Huntington’s (CAG repeats)
• Fragile X (CCG repeats)
![Page 58: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/58.jpg)
Replication Errors and Mutations
• Inheritance of mutations– Harmful mutations
•Individuals may not live to reproductive age
•Individuals may not develop/adapt as well
– Advantageous mutations•Help survival of organism and are passed down if mutation occurred in cells that produce gametes
![Page 59: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/59.jpg)
Genes and cancer
• Cancer is uncontrolled, abnormal cell division– Apoptosis--programmed cell death, which
is necessary for normal functioning
• Cause of cancer?– Genes that control production of new cells
don’t turn off
![Page 60: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/60.jpg)
Genetic causes of cancer
• Oncogenes--cause cell to become cancerous
• Genes become oncogenes in 3 ways– Mutation can occur in a growth-factor gene,
causing rapid, uncontrolled cell growth– Error in DNA replication, producing multiple
copies of a single-growth factor gene– Change in gene’s location--falls under the
control of a different promoter is transcribed more often (producing more growth-factor)
![Page 61: DNA Deoxyribose Nucleic Acid](https://reader036.fdocuments.in/reader036/viewer/2022062422/568131a8550346895d981657/html5/thumbnails/61.jpg)
Tumor suppression
• Humans have tumor-suppressor genes which are natural “anti-oncogenes”– If tumor suppressor gene is mutated, uncontrolled
growth/reproduction occurs
• Retinoblastoma--inheritable cancer in eyes caused by changes in tumor-suppressor gene on chromosome 13– Can also occur when mutations occur in an individual (not
always inherited)
• Identifying location of these genes can increase identification and treatment of cancer