Biology Essential Concepts Genetics: Nucleic Acids

Phosphate Biology Essential Concepts Genetics: Nucleic Acids 5-carbon sugar

Obj 1 Describe the structure of nucleic acids Nucleic acids are complex molecules made of chains of nucleotides. Each nucleotide consists of a 5-carbon sugar, a nitrogen-containing base, and a phosphate group. Nitrogenous Base, either A, G, C, or T

A nucleotide

Nucleotides bond each other, forming a backbone of sugars and phosphates with the bases "dangling" Nitrogenous Base Nitrogenous Base

There are two types of nucleic acids, DNA and RNA.

Obj 2 Distinguish DNA from RNA structurally and functionally

DNA (deoxyribose nucleic acid) RNA (ribose nucleic acid)

DNA’s sugar: deoxyribose RNA’s sugar: ribose

DNA’s bases: RNA’s bases: Adenine (A) Adenine (A) Guanine (G) Guanine (G) Cytosine (C) Cytosine (C) Thymine (T) Uracil (U)

DNA’s shape: RNA’s shape: made of two strands of nucleotides, made of one strand of nucleotides with the bases of the two strands holding them together like a spiral ladder (a double helix)

DNA’s function: RNA’s function: contains coded instructions for making decodes the instructions and the proteins that control a cell's assembles proteins from the activities. instructions provided by DNA Obj 3 Relate DNA to genes, alleles, and chromosomes

Chromosomes are made of longs strands of DNA molecules. Chromosomes are passed from both parents to their offspring and carry inherited instructions that code for the construction of unique individuals.

Particular sections of a chromosome's DNA contain instructions for an inherited trait, for example eye color. A section of DNA that codes for a trait is called a gene .

Different versions of a gene are called alleles. For instance, for the gene that controls eye color, several alleles exist that code for different eye color.

Obj 4 Describe the structure of a chromosome

a chromosome, made of DNA PDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDP  deoxyribose sugar and phosphate backbone A T A G G T G A G C A A G A C A T A G G T G A G  nitrogenous bases, hydrogen bonded to bases T A T C C A C T C G T T C T G T A T C C A C T C of the other strand PDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDP one gene, a section that codes for one trait another gene

The diagram above represents a VERY short chromosome. It is made up of individual nucleotides (a phosphate group, P, a deoxyribose sugar, D, and a base, A, T, G, or C). The nucleotides bond to form long chains of DNA. The "backbone" of a DNA molecule is made of the phosphate groups and deoxyribose sugars. The "rungs" between the backbones are composed of bases. The bases of one strand are "hydrogen bonded" to the bases of its complementary strand (adenine is always paired with thymine and guanine is always paired with cytosine). Instead of being flat, a chromosome twists into a spiral, a shape called a double helix.

Obj 5 Relate DNA replication to its complementary structure

DNA Replication – Unwind, unzip, complement, bond.

The steps in DNA replication (which takes place in the S phase of interphase, remember?) are:

1. Unwind: the double helix unwinds 2. Unzip: enzymes break the hydrogen bonds that hold the base pairs together, separating the two strands 3. Complement: an enzymes (DNA polymerase) matches free-floating nucleotides that complement each strand's bases (adenine to thymine and guanine to cytosine) 4. Bond: bonds form between the sugars and phosphate groups of adjacent nucleotides

Note the two chains of the original DNA serve as templates for two new strands (one new one for each original strand). The two resulting double-helix DNA strands are identical! Phosphate Biology Essential Concepts Genetics: Nucleic Acids 5-carbon sugar

Obj 1 Describe the structure of nucleic acids Nucleic acids are complex molecules made of chains of ______. Each nucleotide consists of a 5-carbon ______, a nitrogen-containing ______, and a ______. Nitrogenous Base, either A, G, C, or T

A nucleotide

Nucleotides bond each other, forming a backbone of sugars and phosphates with the bases "dangling" Nitrogenous Base Nitrogenous Base

There are two types of nucleic acids, DNA and RNA.

Obj 2 Distinguish DNA from RNA structurally and functionally

DNA (deoxyribose nucleic acid) RNA (ribose nucleic acid)

DNA’s sugar: ______RNA’s sugar: ______

DNA’s bases: RNA’s bases: Adenine (A) Adenine (A) Guanine (G) Guanine (G) Cytosine (C) Cytosine (C) ______(T) ______(U)

DNA’s shape: RNA’s shape: made of ______strands of nucleotides, made of _____ strand of nucleotides with the bases of the two strands holding them together like a spiral ladder (a ______)

DNA’s function: RNA’s function: contains coded instructions for making decodes the instructions and the proteins that control a cell's assembles proteins from the activities. instructions provided by DNA Obj 3 Relate DNA to genes, alleles, and chromosomes

______are made of longs strands of DNA molecules. Chromosomes are passed from both parents to their offspring and carry inherited instructions that code for the construction of unique individuals.

Particular sections of a chromosome's DNA contain instructions for an inherited trait, for example eye color. A section of DNA that codes for a trait is called a .

Different versions of a gene are called ______. For instance, for the gene that controls eye color, several alleles exist that code for different eye color.

Obj 4 Describe the structure of a chromosome

a chromosome, made of DNA PDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDP  deoxyribose sugar and phosphate backbone A T A G G T G A G C A A G A C A T A G G T G A G  nitrogenous bases, hydrogen bonded to bases T A T C C A C T C G T T C T G T A T C C A C T C of the other strand PDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDPDP one gene, a section that codes for one trait another gene

The diagram above represents a VERY short chromosome. It is made up of individual nucleotides (a phosphate group, P, a deoxyribose sugar, D, and a base, A, T, G, or C). The nucleotides bond to form long chains of DNA. The "backbone" of a DNA molecule is made of the phosphate groups and deoxyribose sugars. The "rungs" between the backbones are composed of bases. The bases of one strand are "hydrogen bonded" to the bases of its complementary strand (adenine is always paired with thymine and guanine is always paired with cytosine). Instead of being flat, a chromosome twists into a spiral, a shape called a double helix.

Obj 5 Relate DNA replication to its complementary structure

DNA Replication – Unwind, unzip, complement, bond.

The steps in DNA replication (which takes place in the S phase of interphase, remember?) are:

5. ______: the double helix unwinds 6. ______: enzymes break the hydrogen bonds that hold the base pairs together, separating the two strands 7. ______: an enzymes (DNA polymerase) matches free-floating nucleotides that complement each strand's bases (adenine to thymine and guanine to cytosine) 8. ______: bonds form between the sugars and phosphate groups of adjacent nucleotides

Note the two chains of the original DNA serve as templates for two new strands (one new one for each original strand). The two resulting double-helix DNA strands are identical!