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3.6: What Are Nucleotides and Nucleic Acids?

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3.6 What Are Nucleotides and Nucleic Acids?

Nucleotides are the monomers of nucleic acid chains and fall into two general classes

– Deoxyribose nucleotides

– Ribose nucleotides

All nucleotides are made of three parts

– Phosphate group

– Five-carbon sugar

– Nitrogen-containing base

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https://www.khanacademy.org/partner-content/crash-course1/crash-course-biology/v/crash-course-biology-107

ATP-video-2:30-3:30DNA-video 2:00-305

• DNA- https://www.khanacademy.org/partner-content/crash-course1/crash-course-biology/v/crash-course-biology-110

• ATP

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NucleotidesA. Structure 5-C sugar phosphate group nitrogen-containing base

adenine guanine cytosine thymine uracil

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1. Deoxyribose (A, G, C, T)

2. Ribose (A, G, C, U)

Nucleotides: Deoxyribose and Ribose

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Nucleotides: Deoxyribose and Ribose

energy-carrier molecules subunits of polymers called nucleic acids

intracellular messenger molecules

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Nucleotides Act as Energy Carriers

ATP – adenosine triphosphate ribose nucleotide 3 phosphate groups

stores energy in bonds btwn phosphate groups

energy released when last phosphate bond is broken

available energy is then used to drive other rxns (linking amino acids)

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1. ADP + Energy + Phosphate -----> ATP

(stores energy) dehydration synthesis

2. ATP ------> ADP + Phosphate + Energy

(releases energy) hydrolysis

How is ATP made and broken down?

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Nucleotides Act as Intracellular Messengers

cAMP – ribose nucleotide cyclic adenosine monophosphate messenger molecule in cells hormones stimulate cAMP to form within cells

where it initiates biochemical reactions

NAD+ & FAD – electron carriers transport energy in form of high- energy electrons used in ATP synthesis

FADNAD

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Nucleic Acids: DNA and RNA the Molecules of Heredity

Nucleic acids: polymers made up of nulceotides (monomers) linked together via dehydrations synthesis

found in chromosomes

in cells

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Figure 3-23 Deoxyribose nucleotide

phosphate

sugarbase

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Nucleotides: Deoxyribose and Ribose

1. Deoxyribose (A, G, C, T)

2. Ribose (A, G, C, U)

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Figure 3-24 The energy-carrier molecule adenosine triphosphate (ATP)

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3.6 What Are Nucleotides and Nucleic Acids?

Nucleotides act as energy carriers and intracellular messengers

– Adenosine triphosphate (ATP) is a deoxyribose nucleotide with three phosphate functional groups

– Ribose nucleotide cyclic adenosine monophosphate (cAMP) acts as a messenger molecule in cells

– Electron carriers are those nucleotides (NAD and FAD) transporting energy in the form of high-energy electrons

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3.6 What Are Nucleotides and Nucleic Acids?

DNA and RNA, the molecules of heredity, are nucleic acids

– Nucleic acids are polymers formed by monomers strung together in long chains by dehydration synthesis

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3.6 What Are Nucleotides and Nucleic Acids?

DNA and RNA, the molecules of heredity, are nucleic acids (continued)

– There are two types of polymers of nucleic acids

– DNA (deoxyribonucleic acid) is found in chromosomes and carries genetic information needed for protein construction

– Each DNA molecule consists of two chains of nucleotides that form a double helix linked by hydrogen bonds

– RNA (ribonucleic acid) makes copies of DNA and is used directly in the synthesis of proteins

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Figure 3-25 Deoxyribonucleic acid

hydrogenbond