Genes/DNA Flashcards
Which of the following are components of nucleotides?
(a) deoxyribose
(b) amino acids
(c) phosphate
(d) enzymes (e) nitrogenous bases
Deoxyribose and phosphate
Which of the following represent a correct pairing of bases?
(a) adenine with thymine
(b) adenine with guanine
(c) thymine with adenine
(d) guanine with cytosine
(e) thymine with thymine
A,C,D
The building blocks of DNA are:
Nucleotides
Which of the following are nitrogenous bases?
(a) Valine
(b) Guanine
(c) Thymine
(d) Serine
B,C
Replication of DNA occurs
(a) During cell division
(b) before cell division
(c) at any time
B
A nucleotide triplet codes for
(a) a protein
(b) an amino acid
(c) an enzyme
(d) an organic base
A
The sequence of bases in DNA forms the
Genetic code
A group of three bases (_________) controls the production of a particular amino acid in the cytoplasm of the cell
A triplet
Such a sequence forms a
Gene
There may be a _________ or more bases in one gene
Thousands
Cytosine
Adenine
Thymine=
Valine
Cytosine
Guanine
Adenine=
Alanine
Each triplet codes for a specific _______
Amino acid
The sub-units are called
Nucleotides
Each nucleotide is made up of
a sugar called
Deoxyribose
is a sugar, like glucose, but with only five carbon atoms in its molecule
Ribose
is almost the same but lacks one
oxygen atom
Deoxyribose
Both molecules may be represented by the symbol
Pentagon
The most common bases are
Adenine
Thymine
Guanine
Cytosine
The deoxyribose, phosphate and one of the bases
Combine to form a
Nucleotide
When does DNA strands unwind and separate
Before cell division
Each strand makes a new partner by adding the appropriate
Nucleotides
The result is that there are now ________ DNA molecules in the nucleus
Two
Before a cell divides, the DNA strands unwind and separate Each strand makes a new partner by adding the appropriate nucleotides The result is that there are now two double-stranded DNA molecules in the nucleus So that when the cell divides, each nucleus contains identical DNA
This process is called
Replication
The sequence of bases in DNA forms the
Genetic code
CGA=
Alanine
CAA=
Valine
DNA is a what
Chemical substance
DNA controls all the
Chemical changes
The kind of cell which is formed, (muscle, blood, nerve etc) is controlled by ____
DNA
The kind of organism which is produced (buttercup,
giraffe, herring, human etc) is controlled by ______
DNA
is a very large molecule made up of a long chain of sub-units
DNA
