nucleic acid classification

functions of nucleic acids

DNA stores genetic information in the cells of all living things. It contains the genetic code. This is the code that instructs cells how to make proteins. The instructions are encoded in the sequence of nitrogen bases in the nucleotide chains of DNA. RNA copies and interprets the genetic code in DNA and is also involved in the synthesis of proteins based on the code. Click image to the left or use the URL below. URL: Q: DNA is found only in the nucleus of cells, but proteins are synthesized in the cytoplasm of cells, outside of the nucleus. How do you think the instructions encoded in DNA reach the cytoplasm so they can be used to make proteins? A: After RNA copies the instructions in DNA, it carries them from the nucleus to a site of protein synthesis in the cytoplasm, where the instructions are translated into a protein.

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the double helix

RNA consists of just one chain of nucleotides. DNA consists of two chains. Nitrogen bases on the two chains of DNA form hydrogen bonds with each other. Hydrogen bonds are relatively weak bonds that form between a positively charged hydrogen atom in one molecule and a negatively charged atom in another molecule. Hydrogen bonds form only between adenine and thymine, and between guanine and cytosine. These bonds hold the two chains together and give DNA is characteristic double helix, or spiral, shape. You can see the shape of the DNA molecule in the Figure 1.2. Sugars and phosphate groups form the backbone of each chain of DNA. The bonded bases are called base pairs. Determining the structure of DNA was a huge scientific breakthrough. Q: Compare the structure of DNA to a spiral staircase. What part of the molecule do the stair steps represent? A: The steps represent the base pairs.

nucleotides

Nucleic acids consist of chains of small molecules called nucleotides, which are held together by covalent bonds. The structure of a nucleotide is shown in the Figure 1.1. Each nucleotide consists of: 1. a phosphate group, which contains phosphorus and oxygen (PO4 ). 2. a sugar, which is deoxyribose (C5 H8 O4 ) in DNA and ribose (C5 H10 O5 ) in RNA. 3. one of four nitrogen-containing bases. (A base is a compound that is not neither acidic nor neutral.) In DNA, the bases are adenine, thymine, guanine, and cytosine. RNA has the base uracil instead of thymine, but the other three bases are the same.

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what are nucleic acids

Nucleic acids are one of four classes of biochemical compounds. (The other three classes are carbohydrates, proteins, and lipids.) Nucleic acids include RNA (ribonucleic acid) as well as DNA (deoxyribonucleic acid). Both types of nucleic acids contain the elements carbon, hydrogen, oxygen, nitrogen, and phosphorus. Q: Which of the elements in DNA is not identified with any other class of biochemical compounds? A: All biochemical compounds contain carbon, hydrogen, and oxygen; and proteins as well as nucleic acids contain nitrogen. Phosphorus is the only element that is identified with nucleic acids.

instructional diagrams

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The diagram shows the structure of deoxyribonucleic acid (DNA) which carries the genetic information of organisms. DNA is made up of a double helix of two complementary strands. The strands of the double helix are anti-parallel with one being 5' to 3', and the opposite strand 3' to 5'. Each single strand of DNA is a chain of four types of nucleotides. The four types of nucleotide correspond to the four nucleobases adenine, cytosine, guanine, and thymine, commonly abbreviated as A, C, G and T. Adenine pairs with thymine (two hydrogen bonds), and guanine pairs with cytosine (three hydrogen bonds). During DNA replication, the parent DNA unwinds and each parental strand serves as a template for replication of new strands. Nucleobases are matched to synthesize the new daughter strands.

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This diagram shows the structure of a DNA or deoxyribonucleic acid. Deoxyribonucleic acid is a molecule that carries the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. Most DNA molecules consist of two strands coiled around each other to form a double helix. The two DNA strands are composed of simpler units called nucleotides. Each nucleotide is composed of one of four nitrogen-containing compounds either cytosine (C), guanine (G), adenine (A), or thymine (T). The nucleotides are joined to one another in a chain by covalent bonds between the sugar of one nucleotide and the phosphate of the next, resulting in an alternating sugar-phosphate backbone.

questions

nitrogen bases in dna include

-->  a) adenine.

b) uracil.

c) ribose.

d) two of the above

the backbone of a nucleic acid consists of alternating nitrogen bases.

a. true

-->  b. false

functions of rna include

a) copying the genetic code in dna.

b) carrying the genetic code to the cytoplasm.

c) helping to make proteins based on the genetic code.

-->  d) all of the above

dna is found only in the nucleus of cells.

-->  a. true

b. false

diagram questions

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What is the term for connected sugar, phosphate group and protein?

a. hydrogen bond

b. deoxyribose

-->  c. nucleotide

d. sugar-phosphate backbone

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Which component of DNA link adjacent nucleotides together?

a. Hydrogen bond

b. Sugar

-->  c. Phosphate group

d. Adenine

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A DNA strand with the sequence ACTTAGGCAAC is transcribed. What is the sequence of the mRNA molecule synthesized?

a. TUAATCCUTTC

b. TGAATCCGTTG

c. UGUUUCCGUUG

-->  d. UGAAUCCGUUG

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Which is the sugar you can find on DNA?

-->  a. Deoxyribose

b. None. It's only proteic.

c. Phosphate

d. Ribose

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What amino acids can't be paired together?

a. C and G

b. A and T

c. T and A

-->  d. C and A

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What does the green label mean?

a. Thymine

-->  b. Adenine

c. Cytosine

d. Guanine

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What is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters GCAT?

a. Cytosine

b. Guanine

-->  c. Thymine

d. Adenine

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Identify the nitrogenous base that uses two hydrogen bonds to pair with Adenine.

-->  a. Thymine

b. Guanine

c. Cytosine

d. Phosphate

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Which of the following bonds to Thymine?

a. Cytosine

b. Guanine

-->  c. Adenine

d. Hydrogen

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How many amino-acids are there in the DNA?

a. 3

-->  b. 4

c. 5

d. 6

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Identify the complimentary base pair for Adenine?

a. Cytosine

-->  b. Thymine.

c. Deoxyribose

d. Guanine

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What do the small dots symbolize in the centers of protein synthesis?

a. Adenine

b. Cytosine

-->  c. Hydrogen bond

d. Thymine

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How many DNAs are represented in the diagram below?

-->  a. 3

b. 1

c. 2

d. 4

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How many nitrogenous bases does the DNA possess?

a. 5

-->  b. 4

c. 6

d. 3

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How many times did the parental DNA split in this diagram?

a. 4 times

b. twice

-->  c. once

d. 3 times

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How many daughter DNA are there?

-->  a. two

b. four

c. one

d. three

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What does the blue color represent on the diagram?

a. Thymine

b. Adenine

c. Cytosine

-->  d. Guanine

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How many parts of the DNA are shown?

a. 3

-->  b. 5

c. 2

d. 4

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What binds to cytosine?

a. Cytosine.

b. Adenine.

c. Thymine.

-->  d. Guanine.

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Cytosine always bonds with which of the following?

a. Adenine

b. Thymine

c. Sugar Phosphate

-->  d. Guanine

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What base pairs with adenine?

a. Serine

b. Cytosine

c. Guanine

-->  d. Thymine

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What does cytosine bond with to make a complementary base pair?

a. Adenine

b. Sugar phosphate

-->  c. Guanine

d. Thymine

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How many base pairs are there?

a. 2

b. 3

c. 1

-->  d. 4

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In a DNA strand, which material holds all the base pairs together?

a. adenine

b. guanine

-->  c. sugar phosphate

d. cytosine

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In protein synthesis, what is the long twisted tubing called?

a. Adenine

b. Cytosine

-->  c. Sugar phosphate

d. Thymine

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Which nucleobase is labeled with a G?

a. Uracil

b. Adenine

-->  c. Guanine

d. Cytosine

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How many helixes are used to build DNA?

a. 1

-->  b. 2

c. 4

d. 3

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Which base pairs with cytosine?

a. Cytosine

b. Adenine

c. Thymine

-->  d. Guanine

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How many pairings of nucleobases are possible in DNA?

a. 4

b. 1

c. 3

-->  d. 2

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How many types of nucleobases of RNA are there?

a. 5

b. 3

c. 2

-->  d. 4

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In a DNA strand, which material holds all the base pairs together?

a. thymine

b. cytosine

c. guanine

-->  d. sugar-phosphates

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Can you identify the phosphate backbone on this diagram?

a. A

b. 3

-->  c. 1

d. 2

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How many parts of the DNA are shown?

a. 2

-->  b. 3

c. 1

d. 4

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In the diagram, C (cytosine) is what type of material?

a. Sugar phosphate

-->  b. Nitrogenous base

c. Minor groove

d. Major groove

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How many types of nucleobases are found in DNA?

a. Five

-->  b. Four

c. Two

d. Three

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How much width does the DNA structure have?

a. 1nm

b. 3nm

-->  c. 2nm

d. 4nm

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What comes between nitrogenous bases and the minor groove?

a. Complex groove

-->  b. major groove

c. DNA structure

d. sugar phosphate backbone

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What is the width of a Deoxyribonucleic Acid?

a. 0.34 nanometers.

-->  b. 2 nanometers.

c. 1 nanometer.

d. 3.4 nanometers.

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Which is the base pair of guanine?

a. Thymine

b. Adenine

c. Sugar Phosphate Backbone

-->  d. Cytosine

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What is thiamine paired with?

a. cytosine

b. phosphate

-->  c. Adenine

d. guanine

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What makes a base pair with cytosine?

a. sugar phosphate

b. thymine

c. adenine

-->  d. guanine

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How many base pairs are there as shown?

a. four

b. two

-->  c. one

d. three

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How many parts make up the DNA?

a. 5

b. 3

-->  c. 6

d. 4

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In a DNA strand, which material holds all the base pairs together?

a. guanine

b. adenine

c. thymine

-->  d. sugar phosphate

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What does A stand for?

-->  a. Adenine

b. Cytosine

c. Guanine

d. Thymine

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Which nitrogenous base is always paired with adenine?

-->  a. T

b. C

c. A

d. G

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How many combinations of the nitrogenous bases are there?

a. 4

b. 16

-->  c. 12

d. 8

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What are the four types of DNA?

a. ABGT

b. ATGU

c. ADNR

-->  d. ATCG

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What is the picture all about?

a. Photosynthesis

-->  b. Protein Synthesis

c. Energy Source

d. Life Cycle of an Animal

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Which nitrogenous base is labeled C?

a. Guanine

-->  b. Cytosine

c. Adenine

d. Thymine

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Which nitrogen base doesn't appear in the DNA?

a. Thymine

b. Guanine

c. Adenine

-->  d. Uracil

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How many Types of bases are there in a DNA double helix?

a. 2

-->  b. 4

c. 5

d. 3

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What is an impossible base pair?

-->  a. CA

b. There are no impossible base pairs

c. AT

d. CG

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What would happen if the base pairs in the DNA double helix do not match up?

a. DNA does not change base pairs

b. Nothing would happen

-->  c. There will be a mutation in the DNA

d. The DNA would have extra chromosomes

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Identify the nitrogenous base that is always paired with Adenine.

-->  a. Thymine

b. Guanine

c. Adenine

d. Cytosine

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What keeps the base pairs held together?

a. double bonds

b. glue

c. oxygen bonds

-->  d. hydrogen bonds

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What nitrogen base connects to thymine?

a. thymine

b. guanine

c. cytosine

-->  d. adenine

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How many hydrogen bonds like two bases?

a. 2

b. 3

c. None - it's a covalent bond

-->  d. 1

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How many types of nitrogenous bases are found in DNA?

a. 2

b. 5

c. 3

-->  d. 4

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What are weak bonds between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other?

a. Adenine

-->  b. Hydrogen Bonds

c. Base Pairs

d. Guanine

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What holds base pairs together?

-->  a. hydrogen bonds

b. thymine

c. adenine

d. cytosine

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What is the blue bars in the picture below?

-->  a. guanine

b. adenine

c. cytosine

d. thymine