DNA Structure and Replication

Cell Cycle

Describe the stages of the cell cycle, including deoxyribonucleic (DNA) replication and mitosis, and the importance of the cell cycle to the growth of organisms.

Multiple Select

What three things does a cell have to do to go through the cell cycle? (check all three)

• Grow

• Die off to make room

• Make a copy of it's DNA

• Split into two cells

• Compete with neighbor cells

Multiple Choice

During interphase, what happens during the S phase?

• The cell grows

• The cell splits in two

• DNA replicates (makes a copy)

Multiple Choice

Which phase of the interphase does DNA replicate or make a copy of itself?

• G1 phase

• S phase

• G2 phase

​Proteins catalysts. A catalyst speeds up a chemical reaction by lowering the activation energy.

Made of :

​

. Phosphate

. (Deoxyribose) Sugar​

​. Nitrogenous Base

​Nucleotide

Multiple Choice

What is "A"?

• Nucleotide

• Deoxyribose Sugar

• Nitrogenous base

• Phosphate

Multiple Choice

What is "B"?

• Nucleotide

• Deoxyribose Sugar

• Nitrogenous base

• Phosphate

Multiple Choice

What is "C"?

• Nucleotide

• Deoxyribose Sugar

• Nitrogenous base

• Phosphate

Multiple Choice

What is the molecule in the image?

• Nucleotide

• Deoxyribose Sugar

• Nitrogenous base

• Phosphate

Multiple Choice

What do the dotted lines between the nitrogenous bases (A,T,C,G) represent in the image provided?

• Covalent bonds

• Ionic bonds

• Peptide bonds

• Hydrogen bonds

Multiple Choice

What is bonded to Adenine in the image to form a section of the DNA molecule?

• Guanine and Phosphate group

• Cytosine and Deoxyribose sugar

• Thymine and Deoxyribose sugar

• Deoxyribose sugar and Phosphate group

Multiple Choice

What makes up the SIDES of a DNA ladder?

• nitrogen bases

• sugars & phosphates

• genes & chromosomes

• RNA

Multiple Choice

What do organisms have in common?

• DNA sequence made of A,C,T,G

• DNA sequence is in the same order

• DNA sequence between organisms have nothing in common

• DNA sequence made of A,U,C,T,G

A <----> T

​

G <----> C​

​

Complimentary Bases

Multiple Choice

What is the complimentary sequence of the following sequence:

GATCAG

• TGACAT

• GACATG

• CTAGTC

• CGACTA

Multiple Choice

What determines the specific traits in an organism?

• The number of carbons in the DNA molecule.

• The number of hydrogen bonds that hold the strands of DNA together. 

• The sequence of nucleotide bases in the DNA molecule.

• The sequence of phosphates along each DNA strand. 

Fill in the Blank

If one strand of the DNA molecule is A T A C G G C T T C A T A G G, what will the other strand be?

Process of making a, hopefully, identical copy of DNA.

​

​What is DNA Replication

DNA replication happens where DNA is, which is in the nucleus of a cell. Unless that cell is a prokaryote, which does not have a nucleus.

Where: Nucleus

Interphase is the phase of cell life that occurs before mitosis (cell replication) begins, and this is the time that DNA replicates.

When: Interphase

​When and Where?

The purpose of DNA replication is to make an identical strand of DNA to prepare for cell division. This way each new cell has an identical copy of DNA.

​

​Purpose

Drag and Drop

DNA replication occurs during ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

interphase

metaphase

telophase

anaphase

prophase

Key Players in DNA Replication

Enzymes

Most key players in DNA replication are enzymes

Enzymes are a biological catalyst, meaning the speed up a reaction. They are proteins that act upon molecules. The names often end in

-ase.

"Unzips" DNA. It does this by breaking the hydrogen bonds between the base pairs.

​​Helicase

Builds in the complementary base pairs of the DNA strand being replicated

​​Polymerase

Multiple Choice

Which of the following best describes the arrangement of the sides of the DNA molecule

• Bonding

• Alternating

• Anitparallel

• Parallel

Multiple Choice

DNA replication results in

• 2 completely new DNA molecules

• 2 DNA molecules that each contain a strand of the original

• 1 new DNA molecule and 1 old

• 1 new molecule of DNA

Multiple Choice

Enzyme that breaks hydrogen bonds (unzips)

• Ligase

• Polymerase

• Primase

• Helicase

Multiple Choice

DNA strand has the following bases AAGCCA what are the bases on the complementary strand

• GGCTTA

• TTGGGA

• CCAGGT

• TTCGGT

Multiple Choice

What is the complementary strand to this DNA sequence: ATACCGCTG

• TATGGCGAC

• ATACCGCTG

• CGCAATAGT

• GCGTTATCA

Enzymes

Most key players in DNA replication are enzymes

Enzymes are a biological catalyst, meaning the speed up a reaction. They are proteins that act upon molecules. The names often end in

-ase.

Multiple Choice

Of these four molecules, given the names, which would you think is an enzyme?

• Nuclein

• Lactase

• Glucose

• Amino Acid

"Unzips" DNA. It does this by breaking the hydrogen bonds between the base pairs.

​​Helicase

Builds in the complementary base pairs of the DNA strand being replicated

​​Polymerase

​

Primase places markers that tell DNA replication where to begin working.

​​Primase

Connects DNA fragments together

Ligase

Match

Match the following

• Polymerase

• Ligase

• Primase

• Helicase

builds the complimentary DNA strand

bonds DNA fragments together

Indicates whee DNA replication begins

"unzips" the DNA

• builds the complimentary DNA strand

• bonds DNA fragments together

• Indicates whee DNA replication begins

• "unzips" the DNA

For the DNA to fit together the nitrogenous bases will fit together with their complimentary pair. The DNA strands run antiparellel, which is opposite directions. They are labeled 3¹ and 5¹, named for the carbons in the structure. So they run five prime to three prime and three prime to five prime.

​

Complementary and Antiparallel

Steps of ​Building DNA

1. ​DNA Helicase "unzips" the DNA and proteins hold the DNA open.

2. DNA Primase marks the region to begin replication

3. DNA Polymerase begins replication from 5¹ to 3¹ direction

4. On the lagging strand, as the DNA unzips, a primer will set a new starting point and DNA polymerase will begin to replicate at the new location.

   1. As this occurs, the replicated strand is made in fragments

   2. DNA ligase binds these fragments, called Okazaki fragments, together

5. When the process is done there are two strands of DNA.

Reorder

Reorder the following

• DNA is unzipped

• Primase marks region to begin replication

• Polymerase builds complimentary DNA strand

• Ligase bonds DNA fragments

1

2

3

4

• 1
• 2
• 3
• 4

​DNA replication is considered semi-conservative because each new strand contains one copy of the old strand.

Dropdown

After replication, each strand has ​

Select answer

new strand(s) and ​

Select answer

old strand(s).

Multiple Choice

This picture is illustrating the ____ nature of DNA.

• anti-parallel
• deoxyribosic
• helical
• radioactive

Multiple Choice

Which enzyme is responsible for adding nucleotides?

• Topoisomerase

• DNA Polymerase

• Ligase

• Primase

Multiple Choice

Which sequence of DNA bases would pair with this partial strand

CAT TCA CTG

• ATG TGA CAG

• TAC ACT GTC

• GTA AGT GAC

• CAT TCA CTG

Multiple Choice

Which sequence of DNA bases would pair with this partial strand
CAT TCA CTG

• ATG TGA CAG
• TAC ACT GTC
• GTA AGT GAC
• CAT TCA CTG

Drag and Drop

DNA replication occurs during ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

interphase

metaphase

telophase

anaphase

prophase