Docsity
Log inSign up
Docsity
Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity

Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan

Guidelines and tips
Guidelines and tips
Sell on Docsity
Sell on Docsity
Log inSign up

Prepare for your exams

Study with the several resources on Docsity

Find documents

Prepare for your exams with the study notes shared by other students like you on Docsity

Search Store documents

The best documents sold by students who completed their studies

Search through all study resources
Docsity AINEW

Summarize your documents, ask them questions, convert them into quizzes and concept maps

Explore questions

Clear up your doubts by reading the answers to questions asked by your fellow students

Earn points to download

Earn points by helping other students or get them with a premium plan

Share documents
download point icon20 Points

For each uploaded document

Answer questions
download point icon5 Points

For each given answer (max 1 per day)

All the ways to get free points
Get points immediately

Choose a premium plan with all the points you need

Study Opportunities

Choose your next study program

Get in touch with the best universities in the world. Search through thousands of universities and official partners

Community

Ask the community

Ask the community for help and clear up your study doubts

University Rankings

Discover the best universities in your country according to Docsity users

Free resources

Our save-the-student-ebooks!

Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors

From our blog

Exams and Study
Go to the blog

Molecular Biology: The Study of DNA, RNA, and Protein Synthesis - Prof. Marianne Mcnamara, Study notes of Biology

Suffolk County Community CollegeBiology
Prof. Marianne Mcnamara

An overview of molecular biology, focusing on the structure and function of dna and rna, the process of dna replication, and the central dogma of molecular biology, which describes how genetic information is transcribed into rna and translated into proteins.

Typology: Study notes

Pre 2010

Uploaded on 12/12/2009

god-7
god-7 🇺🇸

23 documents

1 / 57

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Molecular Biology
•Molecular biology is the study of DNA
–Its structure
–How it replicates (and assembles to create
genetically-distinct offspring)
–How it controls the cell by directing RNA and
protein synthesis
•How does DNA store genetic information,
copy it, and pass it along from one generation
to the next?
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe
pff
pf12
pf13
pf14
pf15
pf16
pf17
pf18
pf19
pf1a
pf1b
pf1c
pf1d
pf1e
pf1f
pf20
pf21
pf22
pf23
pf24
pf25
pf26
pf27
pf28
pf29
pf2a
pf2b
pf2c
pf2d
pf2e
pf2f
pf30
pf31
pf32
pf33
pf34
pf35
pf36
pf37
pf38
pf39

Partial preview of the text

Download Molecular Biology: The Study of DNA, RNA, and Protein Synthesis - Prof. Marianne Mcnamara and more Study notes Biology in PDF only on Docsity!

Molecular Biology

  • (^) Molecular biology is the study of DNA
    • (^) Its structure
    • (^) How it replicates (and assembles to create genetically-distinct offspring)
    • (^) How it controls the cell by directing RNA and protein synthesis
  • (^) How does DNA store genetic information, copy it, and pass it along from one generation to the next?

DNA and RNA

  • (^) DNA and RNA are nucleic acids consisting of long chains of nucleotides (collectively called a polynucleotide)
  • (^) There are 4 types of nucleotides that make up DNA, each with a different nitrogenous base - (^) Adenine (A) - (^) Cytosine (C) - (^) Thymine (T) - (^) Guanine (G)

DNA and RNA

  • (^) RNA has the nitrogenous base Uracil (U), instead of Thymine (T), and is usually single- stranded
  • (^) DNA is double-stranded and forms a double helix
  • (^) The 2 sugar-phosphate backbones that form the double helix run in opposite directions (5’ to 3’ and 3’ to 5’)

Hydrogen bond Base pair Ribbon model Partial chemical structure Computer model Each strand of DNA runs in opposite directions

DNA Replication

  • (^) The human genome (all genes collectively) contains over 6 billion base pairs in 46 chromosomes (23 ‘homologou’s pairs)!
  • (^) Yet, DNA replication requires only a few hours and is astonishingly accurate
  • (^) How does this process occur and what controls it???

Origin of replication Parental strand Daughter strand Bubble Two daughter DNA molecules

DNA Replication

  • (^) Eukaryotic DNA has many origins of replication shortening the overall time needed for the replication process
  • (^) Replication occurs in “bubbles” of parental (old) and daughter (new) DNA
  • (^) Eventually, all the “bubbles” merge yielding 2 completed daughter strands of DNA Daughter strands (grey); Parental strands (blue)

3end 5 ^ end 5end^3 ^ end 35241  35241  P P P P P P P P

Parental DNA 35DNA polymerase molecule Daughter strand synthesized continuously 3535Daughter strand synthesized in pieces

  • (^) Since the 2 DNA strands run in opposite directions, and replication always begins at the 3’ end, the new daughter strand will be laid down beginning at its 5’ end
  • (^) 1 daughter strand is synthesized continuously, while the other must work outward from the forking point

Thank you, polymerases

  • (^) DNA polymerases also carry out a proof- reading step to quickly remove any nucleotides that have been paired incorrectly during replication
  • (^) DNA polymerases and ligases are also involved in repairing DNA damaged by harmful radiation or toxic chemicals, including those found in cigarette smoke!

DNA Replication

  • (^) DNA replication ensures that all cells in a multicellular organism carry the same genetic information
  • (^) DNA replication occurs during interphase!
  • (^) The DNA genotype is expressed as proteins, which provides the molecular basis for phenotypic traits - (^) DNA dictates the synthesis of proteins which determine the traits physically expressed by an organism

Cytoplasm Nucleus DNA Transcription of DNA into RNA RNA Translation of RNA into Protein Protein

DNA is transcribed into RNA and

translated into Protein

  • (^) In eukaryotic organisms, DNA is stored in the nucleus where it is transcribed into RNA; a process called transcription
  • (^) RNA translates the information from DNA into proteins in the cytoplasm (or to be more precise, in the ribosomes… we’ll come back to this); a process called translation