Download NUCLEOTIDE BASE PAIR GENE NUCLEIC ACIDS CHROMOSOME

Unit 6 Notes: Nucleic Acids & DNA Replication Sheet
Name: _________________________________
NUCLEOTIDE
The monomer (building block) of a
nucleic acid. Contains 3 parts:
1. Sugar
2. Phosphate group
3. Nitrogen base
R
N
A
D
N
A
BASE PAIR
Two complementary bases held
together by weak hydrogen bonds.
R
N
A
D
N
A
GENE
A section of DNA on a chromosome
that codes for a trait (e.g. eye color,
height)
NUCLEIC ACIDS
Genetic material passed from parent
to offspring.
RNA
1. Single stranded
2. Ribose sugar
3. Uracil
DNA
1. Double stranded
2. Deoxyibose sugar
3. Thymine
CHROMOSOME
A segment of genetic material
composed of DNA.
SISTER CHROMATIDS
The 2 halves of a doubled
chromosome. Only occur during cell
division.
HOMOLOGOUS CHROMOSOMES
Pairs of doubled chromosomes seen
during meiosis.
Spindle fibers
attach at
centromeres to
pull chromatids
apart
Unit 6 Notes: Nucleic Acids & DNA Replication Sheet
Name: _________________________________
DNA Replication / Synthesis
PURPOSE: To make an extra copy of DNA during S-Phase of the cell cycle for
cellular reproduction (mitosis or meiosis). This ensures each new
daughter cell has an exact copy of DNA as the original parent cell.
Too much change (mutation) in the DNA sequence may result in
cancer.
New strand
Old strand
Weak hydrogen bonds
BASE-PAIR RULES
A=T
G≡C
Old strand
Base Pair
New strand
Nucleotide:
1. Phosphate group
2. Deoxyribose sugar
3. Nitrogen base (A,T,C,G)
Replication fork
Semi-Conservative Replication
1 new strand & 1 old, saved strand
of DNA makes up each strand of
the new DNA molecule.