DNA
CO-OPERATIVE CLOZE PASSAGE
Students work in pairs. Each student has a different cloze passage to complete but the complete
passage can be found by combining the two passages. Students sit opposite each other and read the
incomplete passage which allows the other student to complete the passage. They may not show the
other student the passage.
ORIGINAL PASSAGE
The key to life
Deoxyribonucleic acid, DNA, can be called a biological instruction manual. In almost every cell,
this giant molecule holds the information an organism needs to produce the necessary proteins
required by living things. Shaped like a spiral staircase, DNA is housed in the nucleus of the cell.
DNA is made up of repeating nucleotides. A nucleotide is made up of a phosphate, a sugar
(deoxyribose) and a nitrogen base. There are four bases: adenine, guanine, cytosine and thymine
and specific base-pairing rules apply. Adenine always pairs with thymine, and guanine always pairs
with cytosine. The code for the instruction manual is the order of the bases, which is unique for
each protein. The sugar/phosphate bonding produces the coiled shape of the molecule. The “sides”
of the DNA ladder are made of repeating sugar/phosphate units. The sugar is the link between the
phosphates and the bases. When DNA replicates, or reproduces, it unzips to allow new bases to
attach to each half. This results in the formation of two new identical strands.
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CLOZE PASSAGE 1
The key to life
Deoxyribonucleic acid, ______, can be called a biological instruction manual. In every ______, this
giant molecule holds the _______________ an organism needs to produce the necessary
___________ required by living things. Shaped like a spiral staircase, DNA is housed in the
_____________ of the cell. DNA is made up of repeating nucleotides. A _______________ is made
up of a phosphate, a sugar (deoxyribose) and a nitrogen _____________. There are ___________
bases: adenine, guanine, cytosine and thymine and specific base-pairing rules apply. Adenine
always pairs with thymine, and guanine always pairs with ______________. The code for the
instruction manual is the order of the ___________, which is unique for each protein. The
sugar/phosphate bonding produces the coiled shape of the molecule. The “sides” of the DNA ladder
are made of repeating sugar/phosphate units. The sugar is the link between the phosphates and the
bases. When DNA replicates, or _______________, it unzips to allow new bases to attach to each
half. This results in the formation of __________ new identical strands.
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CLOZE PASSAGE 2
The key to life
Deoxyribonucleic acid, DNA, can be called a _____________ instruction manual. In every cell, this
giant ________________ holds the information an ________________ needs to produce the
necessary proteins required by living things. Shaped like a _____________ staircase, DNA is
housed in the nucleus of the _________. DNA is made up of repeating _______________. A
nucleotide is made up of a _______________, a sugar (deoxyribose) and a nitrogen base. There are
four bases: adenine, guanine, cytosine and thymine and specific base-pairing rules apply. Adenine
always pairs with ______________, and guanine always pairs with cytosine. The code for the
instruction manual is the _____________ of the bases, which is unique for each protein. The
sugar/phosphate bonding produces the coiled shape of the molecule. The 'sides' of the DNA ladder
are made of repeating sugar/phosphate units. The sugar is the link between the phosphates and the
___________. When DNA replicates, or reproduces, it unzips to allow new ______________ to
attach to each half. This results in the formation of two new ___________ strands.
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