Biology Basics DNA and RNA

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What are the building blocks of nucleic acids?

What are the building blocks of DNA?

What are the building blocks of RNA?

What are the compositions of DNA?

What direction does the two DNA strands go?

DNA Molecule width?

A single DNA molecule's dimensions are?

How is the DNA chain assembled?

How is the RNA chain assembled?

Summarize of DNA and RNA:

What are the building blocks of nucleic acids?

What is the main function of the phosphate group?

What are the hydrogen bonds there for?

DNA strand opposite directions: Antiparallel

Formation of DNA:

Summary of DNA:

Summary of RNA:

DNA Replication Summary Steps:

What is Transcription Process?

Translation Process?

What is Gene Regulation?

Sickle Cell Anemia

Deoxyribose - Deoxy sugar + Loss of oxygen atom, H (Carbon 2).

Ribose - Includes oxygen + Hydroxide, OH (Carbon 2).

Phosphate group = Nitrogen base + Deoxyribose = Deoxyribonucleotide

Pyrimidines + Purines

Pyrimidines = Cytosine + Thymine

Purines = Guanine + Adenine

Pyrimidines & Purines

Pyrimidines = Cytosine + Thymine

Purines = Uracil + Adenine

Double stranded, right handed, double helix.

Sugars and phosphates = backbone

Bases pairs are inside the backbone.

Two DNA strands are anti-parallel (opposite directions) = 5' to 3' direction & 3' to 5' direction.

Purine + Pyrimidine:

A + T other strand is G +C = width of DNA molecule.

Width: 22 to 26 Angstroms.

Length: Phosphate + Sugar + Base Pairs = 3.4 Angstroms

10.4 nucleotide units = One full DNA helix = 34 Angstroms.

Assembled using deoxyribonucleotide triphosphates.

1) At the 3' end of DNA = deoxyribonucleotide triphosphates are inserted.

2) Diphosphate is removed to give energy.

3) Deoxyribonucleotide monophosphate remains in DNA backbone.

Assembled using ribonucleotide triphosphates.

1) At the 3' end of RNA = ribonucleotide triphosphates are inserted.

2) Diphosphate is removed to give energy.

3) Nucleotide Monophosphate remains in DNA backbone.

Phosphate group + sugar + nitrogen base = nucleotides.

Phosphate groups connect sugars to form two strands of nucleotides.

Hydrogen bonds between nucleotides = join two nucleotide strands together -> Adenine + Thymine and Cytosine + Guanine.

End of DNA strand = 5' to 3' direction or 3' to 5' direction.

Double-stranded helix.

Double-helix = twisted ladder

Phosphate backbone opposite direction: 5' and 3' / 3' and 5'

Chromosome 1 = largest chromosome = 247 million base pairs

Somatic cells = 46 DNA cells (Any cell of the body except egg and sperm cells)

Somatic cells are diploid = contain two sets of chromosomes, one from each parent.

5' -AGGTCCG- 3' = 3' -TCCAGGC- 5'

Sugar phosphate backbone + nucleotide bases

Single-strand molecule

Ribose = one more oxygen

Uracil bonds with Adenine instead.

Every cell of our body has the same copy of the same DNA.

Using half of the original template to build the molecule.

Helicase = Unzip DNA's genes = unwinding double helix = break down weak hydrogen bonds

Replication Fork = point where splitting starts

Leading Strand (5' and 3') = DNA polymerase adds matching nucleotides

DNA Polymerase = needs a primer called RNA primase -> a thing that DNA polymerase hooks onto to start. *stepping ladder

DNA Polymerase = can only add nucleotides in the 5' and 3' direction.

Lagging Strand (3' and 5') = Copied through segments using RNA Primase (short RNA strand = Okazaki Fragments) so DNA polymerase can work backwards.

Another kind of DNA Polymerase replaces all RNA primers to DNA strands.

DNA ligase = Fragments are joined together.

DNA Polymerase = Proofread and remove nucleotides that are mismatched.

Titin = Chromosome 2

Upstream sequence (3' and 5')= Where the transcription unit begins.

Promoter = upstream sequence = contains two of either: Adenine, Thymine, Guanine and Cytosine

TATA Box = TATAAAA -> ATATTTT

Downstream sequence = 5' and 3' direction.

RNA Polymerase = 1) Binds to the DNA at the TATA Box 2) Unzips the double-helix. 3) copies the DNA sequence downstream of the TATA Box towards the 5' end to make messenger RNA 4) Reaches termination signal that triggers it to pull off

mRNA = short copy of the TATA Box = Guanine is added to 5' end = 5' cap + Poly-A tail attaches to 3' end. = easier for mRNA to leave nucleus.

DNA contains lots of misleading information

RNA splicing = cuts out any misleading information from the recipe book (DNA) like editing.

Two key players of RNA splicing/editing:

Snurps -> Small Ribonucleic Proteins = RNA + proteins = recognizes the start and end of areas to be spliced.

Spliceiosomes = A bunch of Snurps + other proteins that do the actual editing = break junk segments down so that their nitrogenous bases can be reused in RNA or DNA.

Exons = gets spliced together as they'll eventually be expressed = the good parts of the video.

Introns = junk segments that gets cut out + stays in the nucleus to be recycled.

After being protected and refined -> mRNA can be released.

Read the notes, make the machinery and assemble the units.

Processed mRNA gets fed into ribosomes.

Ribosomes = protein + ribosomal RNA (rRNA)

rRNA -> workspace = binding sites that allow incoming mRNA to interact with transfer RNA

transfer RNA = tRNA and translates language of nucleotides to language of amino acids.

1) starting at the 5' end, mRNA slides into ribosome

2) ribosome reads the mRNA three letters at a time = triplet codon

3) Ribosome finds the matching piece = a tRNA with three bases that match the triplet codon = anticodon

4) tRNA brings in the amino acid of the matching bases

5) Polypeptide chain = very beginning of the protein

6) Folding = contort into complex shapes = protein

Primary Structure = one amino acid covalently bonded to another = hold hands with one amino acid = sequence.

Secondary Structure = wrinkled sheets.

Tertiary Structure = bonding and bending 3-D shape = bonding between R groups.

Quaternary Structure = Multiple Proteins = hemoglobin.

Peptide Bond = between two AA and tRNA for 1st AA released.

Transcriptional Regulation = Determines which genes are translated

Regulation after transcription = Determines types and availability of mRNAs to ribosomes

Translation Regulation = Determines rate at which proteins are made.

Regulation after translation = Determines availability of finished proteins.

Mutation in the hemoglobin gene

Hemoglobin (HbA) = Alpha globin + Beta globin

Point Mutation = alters beta globin -> hemoglobin molecules to stick together.

Normal hemoglobin = two alpha globin + two beta globin

Sickle-Cell Anemia = Alpha globin is normal + beta globin carries a mutation

Red blood cells sickle during reduced oxygen levels.

Normal Hemoglobin = Amino Acid 6 = CTC = GAG

Sickle Cell = Amino Acid 6 = CAC = GUG

Rapid Destruction of Sickle Cells = Anemia + Overactivity of bone marrow + Increase Bone Marrow = Weakness and fatigue + Skull deformation

Gene for beta chain = 1) HbE = embryonic 2) HbF = fetal 3) HbA = adult (sickle cell mutation in HbA)