Chapter 22 and GHW#12 Questions Nucleic Acid. Nucleic acids A nucleic acid is a polymer in which the...

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Chapter 22 and GHW#12 Questions

Nucleic Acid

Nucleic acidsA nucleic acid is a polymer in which the monomer units are nucleotides. There are two Types of Nucleic Acids: DNA: Deoxyribonucleic Acid: Found within cell nucleus for storing and transfering of genetic information that are passed from one cell to other during cell divisionRNA: Ribonucleic Acid: Occurs in all parts of cell serving the primary function is to synthesize the proteins needed for cell functions.

pentoseNucleotide

Heterocyclic Bases

PhosphateDeoxyribose Ribose

Nucleotide Formation

Nucleotides

1) Give the names of names of pentose sugars written in Fisher projections (linear form) below

2) Give the names of names of pentose sugars written in Haworth projections (cyclic hemiacetal form) below. (Label the carbon atoms)

Four types of DNA nucleotides

3) Give the names of names of bases and identify them as purines and pyrimidines (Label the atoms in the ring)

Naming DNA Nucleotides

Name Base Nucleoside 5'-NucleotidedAMP Adenine 2'-Deoxyadenosine 2'-Deoxyadenosine-5'-

monophosphate

dCMP Cytosine 2'-Deoxycytidine 2'-Deoxycytidine-5'-monophosphate

dGMP Guanine 2'-Deoxyguanosine 2'-Deoxyguanosine-5'-monophosphate

dTMP Thymine 2'-Deoxythymidine 2'-Deoxythymidine-5'-monophosphate

4)a) What is phosphate and phosphate mono/di-esters?

b) What is a nucleotide?

c) Draw the structure of dAMP and GMP

Primary Structure

DNA Double Strands (secondary stucture)

DNA Double Strand Complimentary Base Pair Hydrogen Bonding

Weak Hydrogen Bonding

5) Draw the following

a) Backbone of a nucleic acid

b) DNA sequence 5'-TGA CGG TAC CC-3'

6) What are the difference between DNA and RNA? DNA RNA number of strands

sugar used

bases used

base pairs

possible locations

full name

Current Interests• DNA structure and types• Gene Expression• Gene Replication• Genome Project• Cancer and Aging• Forensic and Archeology• Epigenetic• Biotechnology• Recombinant-transgenic DNA• Cloning and Stem Cell Research• Bio-ethics

Replications

Human ChromosomesEukaryotic

Prokaryotic

Gene Expression

The process by which information from a gene is used in the synthesis of a functional gene product: Proteins

• Transcription• RNA processing• RNA export• Translation• Folding• Protein transport

Five types of RNARNA molecules found in human cells are categorized into five major types, distinguishedby their function. • Heterogeneous nuclear RNA (hnRNA), • Messenger RNA (mRNA)• Small nuclear RNA (snRNA)• Ribosomal RNA (rRNA)• TransferRNA (tRNA).

RNA Functions

Protein Synthesis

3-base code (triplet) is an “anticodon”Protein moleculeAttached amino acid that is carried from cytoplasm to ribosomes

7) Write the type of RNA used for each of the following functions: a) Makes up parts of the ribosome

b) Delivers amino acid to the ribosomes

c) Codes for proteins

8) What is the name given to the short (6 10 bp) sequence of bases in the RNA prior to the start of transcription to which the RNA polymerase binds?

9) (a) How many nucleotides make up a codon?

(b) How many different codons are there?

(c) How many different amino acids are there?

10) Write the RNA sequence transcribed from the following DNA sequence. Then write the amino acid sequence of the protein translated from that RNA.

5'-TGA TTT CGG TAC GAT TAA CAA CCT CGA ATT CC-3'

11) What causes the variation in traits that is the basis for evolution?

13)(a) What is gene expression? (b) Why is gene expression regulated?

14) For each of the following mutations in the DNA sequence below, show and explain the effect that the mutation will have on the RNA and protein sequence and, if applicable, on the protein in general. (The numbers for each

correspond to the arrows above the sequence.)5'-TGA TTT CGG TAC GAT TAA CAA CCT CGA ATT CC-3'a) T in GAT is replaced by C

b) T in TAA is replaced by C

c) first A in TAA is replaced by G

d. C in CAA is replaced by Ae) delete CAA

f) delete T in GAT

Epigenetics• the term refers to gene expression caused by

mechanisms other than changes in the underlying DNA sequence, hence the name epi- (Greek: επί- over, above).

• neo-Lamarckism: genetic materials in the cytoplasm: environment led to adaptive changes that were passed on.

• Genogrphics: Mitochondrial Eve

The RNA Codons

Polyunsaturated fatty acids: omega-3 and omega-6 fatty acids

Essential Fatty Acids (EFA).

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