#20 DNA & RNA Standard 5A Focus Lesson

DNA Double Helix

Single Stranded

RNA

5A. Know structures and functions of DNA, RNA

and protein.DNA Functions: 1. DNA carries genetic info from one generation to the next.2. DNA becomes read and transcribed so that proteins are made and traits are expressed.3. DNA must be replicated each time cells divide.

Double Helix DNA

Watson and Crick had discovered that DNA was a double helix in which hydrogen bonds between C-G and A-T held the double strands together.

DNA Structure (double helix where two DNA strands are wound around each other.)Nucleic Acids (DNA & RNA) are made up of patterns of monomers called nucleotides.

C

CH2

O

Phosphate Group

Deoxyribose

Nitrogenous Base

Nucleotide Parts

There are two types of nitrogenous bases.Purines- have two rings. Adenine and Guanine

Pyrimidines- have only one ring.Thymine & Cytosine

Pyrimidines Purines

RNA

Single Stranded RNA

There is no thymine in RNA

Pyrimidines Purines

RNA StructureRNA is made of nucleotides. These nucleotides are made up of a Ribose sugar, a phosphate group and a nitrogenous base.

RNA Function-RNA helps to assemble amino acids into proteins. It’s the proteins that determine traits.Three types-mRNA, rRNA and tRNA.

Ribosomal RNA (rRNA) along with several dozen proteins make up the ribosomes. The ribosomes are where proteins are assembled during a process called translation.

Most genes contain instructions for assembling amino acids into proteins. mRNA (messenger RNA) is the RNA molecule that carries copies of DNA instructions for a specific protein.

mRNA is the “blueprint” for assembling the correct proteins in the ribosomes.

tRNA (transfer RNA) is responsible for transferring a specific amino acid to the ribosome for protein synthesis.Three Differences between DNA and RNA1. Sugar is ribose in RNA and deoxyribose in DNA.2. RNA is single stranded and DNA is a double stranded helix.3. RNA contains uracil instead of thymine found in DNA.

Proteins

Proteins control chemical reactions and the phenotypes (traits) of organisms.

Protein Function:1. Proteins control

rate of chemical reactions and regulate our cell functions. It’s these functions that determine what we look like and do.

1. The following molecule is a/an?A. Amino Acid

B. Carbohydrate

C. DNA

D. RNA

2. The following is a monomer of DNA?A. Amino Acid

B. Hydrogen bond

C. Protein

D. NucleotideC

CH2

O

Phosphate Group

Deoxyribose

Nitrogenous Base

3. How many different types of RNA are involved in protein synthesis?A. 1

B. 2

C. 3

D. None

Single Stranded RNA

4. Which of the following have hydrogen bonds between nitrogenous bases?A. DNA

B. RNA

C. A and B

D. None of the above

5. Which of the following represent the initials for the following?tRNA,rRNA and mRNAA. Transition,ribosomal& messenger

B. Transfer, reconnaissance & messenger

C. Transfer,ribosomal & methione

D. Transfer,ribosomal & messenger

6. Which of the following is found in both DNA & RNA?A. phosphate group + guanine + uracil

B. phosphate group + guanine + cytosine

C. ribose + phosphate group + uracilD. deoxyribose + phosphate group + thymine

7. Which of the following describes the structure of DNA?A. Double stranded RNA molecule.

B. Double Stranded Helix molecule.

C. Double stranded RNA helix.

D. Single stranded RNA molecule.