test 5 Flashcards
nucleic acid
the macromolecule that holds our genetic materical (DNA), contains genes (two types: DNA and RNA)
nucleotide
make up the nucleic acids (the monomer or buliding blocks) 3 parts- sugar, phosphate, and a nitrogen base
chromosome
tightly coiled strands of DNA
gene
a section of DNA that has instructions to code for a protein (one chromosome contains thousands of genes)
DNA replication
the process of making an identical copy of DNA (happens in Synthesis phate of interphase)
semi- conservative replication
when part of a molecule is conserved/ saved in replication
what sugar does DNA have?
deoxyribose
what sugar does RNA have?
ribose
what nitrogen bases does DNA have?
-adenine
-thymine
-guanine
-cytosine
what nitrogen bases does RNA have?
-adenine
-uracil
-guanine
-cytosine
what is the shape of a DNA molecule?
double helix
what is the shape of a RNA molecule?
single strand
what are two similarites between DNA and RNA? what is the main similarity between DNA and RNA?
- they both have adenine, guanine, and cytosine and nitrogen bases (main similarity)
- they are both nucleic acids
what are three differences between DNA and RNA?
-DNA has thymine, RNA has uracil
-DNA has deoxyribose as the sugar, RNA has ribose as the sugar
-DNA is shaped like a double- helix, RNA is a single strand
what are the base pairing rules of DNA?
adenine goes with thymine (apples in trees), and cytosine goes with guanine (cars in garages)
what are the base paring rules of RNA?
adenine goes with uracil (apples under trees), and cytosine goes with guanine (cars in garages)
what are hydrogen bonds between?
nitrogen bases
why is it important to have hydrogen bonds between nitrogen bases?
so the DNA molecule can easily unzip because hydrogen bonds are weaker, which is the first step in DNA replication
where are covalent bonds on a DNA molecule?
nucleotides (in between one sugar, one phosphate, and one nitrogen base)
why is it important to have covalent bonds in between nucleotides?
because covalent bonds are stronger and hold together the phosphate-sugar backbone. it also holds the nitrogen bases in order, and if they get out of order then they can’t code for a protein. (the orer of base- pairs codes for a protein)
describe what a nucleotide might look like.
a circle (phosphate) connected to a pentagon (sugar) connected to a square (nitrogen base)
what are the three steps in the process of DNA replication? describe them.
-Unzip the DNA in between the nitrogen bases (hydrogen bonds)
-Enzymes help find complementary bases and bind them according to base pairing rules
-Two identical DNA molecules are formed, each with an “old” strand and a “new” strand
why is DNA replication important?
if we didn’t replicate our DNA each of the two new daughter cells we form would only have 1/2 of our DNA instead of the full thing and wouldn’t be able to function
why is DNA replication considered to be “semi-conservative”?
-because part of the original molecule is saved/ conserved
-each of the two new molecules have one “old” strand of DNA and one “new”
-“old” strands are used as templates for “new” ones
what is the relationship between DNA, chromosomes, and genes?
-genes are pieces/sections of DNA
-there are thousands of genes on a chromosome
-chromosomes are long strands of DNA all bunched up
where do you find DNA in a eukaryotic cell?
in the nucleus
where do you find DNA in a prokaryotic cell?
in the cytoplasm
what macromolecule is DNA?
nucleic acid
what is the monomer of DNA?
nucleotides
