Chapter 2 - Genes and Genetic Diseases Flashcards
What are chromosomes made of?
one long DNA molecule
What are the functional regions of DNA?
genes
DNA is a ____________ model
double-helix
How many protein coding genes do humans have?
20 000
What are the two strands in DNA held together by?
hydrogen bonds
What makes up the “backbone” of DNA?
deoxyribose-phosphate molecules
What makes up the “rungs” of a DNA molecule?
nitrogen bases
Adenine pairs with ______
Thymine
Guanine pairs with ______
Cytosine
Antiparallel
DNA strands run in opposite directions but parallel to one another
What is the purpose of the antiparallel nature of DNA?
one strand serves as a template for the creation of the second strand
Negative strand is a template for making the ________ strand
positive
Positive strand is a template for making the _________ strand
negative
Where is the parent strand broken to begin replicating?
replication fork
Nucleotide
building block of DNA and RNA composed of a sugar, nitrogen base, phosphate group
What is the result of DNA replication?
two identical copies of original DNA
What is a codon?
a pairing of 3 sequential nitrogen bases that code for a specific amino acid
How many types of amino acids does the body contain?
20
What makes up a protein?
a specific combination of amino acids
What is transcription?
when DNA gene sequence is copied to make an mRNA molecule
What is translation?
decoding of mRNA into amino acids to create proteins
What organelle translates proteins?
ribosomes
What is the primary end product of translation?
enzymes
What is RNA called when it moves out of the nucleus? Where does it go?
It is called mRNA and it goes to the ribosomes
What does the “m” in mRNA stand for?
messenger
What does mRNA deliver to the ribosome?
the “recipe” for making new proteins
What does transfer RNA (tRNA) do?
transport anticodon amino acids to ribosomes