chap 13 study Flashcards
What are DNA and RNA?
Nucleic acids that store and transfer genetic information.
What is the monomer (building block) of nucleic acids?
A nucleotide.
What are the three parts of a nucleotide?
Phosphate group, sugar molecule, nitrogenous base.
What sugar does DNA contain?
Deoxyribose.
What sugar does RNA contain?
Ribose.
Is DNA single-stranded or double-stranded?
Double-stranded.
Is RNA single-stranded or double-stranded?
Single-stranded.
What are the nitrogenous bases in DNA?
Adenine, Thymine, Guanine, Cytosine (A, T, G, C).
What are the nitrogenous bases in RNA?
Adenine, Uracil, Guanine, Cytosine (A, U, G, C).
What does mRNA stand for and do?
Messenger RNA – carries genetic code to ribosomes.
What does tRNA stand for and do?
Transfer RNA – brings amino acids during protein synthesis.
What does rRNA stand for and do?
Ribosomal RNA – helps make up the ribosome.
What is complementary base pairing in DNA?
A pairs with T, G pairs with C.
What replaces thymine (T) in RNA?
Uracil (U).
When does DNA replication occur?
During the S phase of the cell cycle.
What does DNA polymerase do?
Builds the new strand, proofreads, and fixes mistakes.
What is the shape of DNA called?
A double helix.
What does semi-conservative replication mean?
Each new DNA has one old strand and one new strand.
What are telomeres?
Protective caps at the end of chromosomes that prevent damage.
Where is DNA stored in prokaryotic cells?
In the cytoplasm.
Where is DNA stored in eukaryotic cells?
In the nucleus.
How does DNA replication start in prokaryotes?
From one point and goes in two directions until it’s done.
How does DNA replication work in eukaryotes?
Starts at many points and replicates in multiple sections at the same time.
