DNA Isolation and Structure Lab 4

What components make up a nucleotide in DNA?

Which base pairs with adenine in DNA?

What is a diploid cell?

During which stage of the cell cycle does DNA replication occur?

How many chromosomes are found in a human diploid cell?

Which enzyme is primarily responsible for unwinding the DNA strand during replication?

What forms the sides of the DNA ladder structure?

What happens to DNA during interphase?

What is the method of DNA replication where half of the old strand is preserved?

Which technique is used to isolate DNA from strawberries?

What component forms the backbone of a DNA molecule?

What observation indicates that DNA has been successfully extracted from strawberries?

How many copies of each chromosome do strawberries have, contributing to the yield of DNA?

Which of the following best describes a nucleotide in DNA?

What is the primary function of DNA?

What should you avoid doing while layering the ethanol during the DNA extraction process?

DNA Isolation, Structure, and Technology Lab 4

Objectives: Understand DNA isolation from plants, DNA structure, DNA fingerprinting processes, DNA molecule construction, and base pairing. Demonstrate DNA fingerprinting using diagrams.

Introduction to DNA Structure

DNA is a double-stranded molecule composed of nucleotides.
Each nucleotide contains a sugar (deoxyribose), a phosphate group, and a nitrogenous base.
Four nitrogenous bases: adenine, thymine, guanine, and cytosine.
Adenine pairs with thymine, and guanine pairs with cytosine.
The alternating sugar-phosphate groups form the sides of a DNA "ladder."
Nitrogenous bases form the rungs of the ladder.
The ladder is twisted into a helix shape.

DNA Function

DNA is the genetic material in the nucleus of cells.
DNA, along with attached proteins, makes up chromosomes.
Eukaryotic cells have homologous chromosome pairs.
Humans have 23 pairs of homologous chromosomes (46 total in diploid cells.).
DNA replication occurs during interphase of the cell cycle.
The process involves making an exact copy of DNA using enzymes and following base-pairing rules.
DNA replication is semi-conservative, meaning each new DNA molecule includes one original strand and a newly synthesized strand.

DNA Isolation Procedure

Strawberries are a good source for DNA extraction due to their soft cell walls and multiple copies of DNA.
Procedure involves smashing strawberries in a Ziploc bag and adding a lysis buffer.
Mixture is filtered through cheesecloth into a beaker.
Ethanol is carefully poured into a test tube with the strawberry extract.
A white DNA layer will form at the ethanol/extract interface.

This quiz focuses on DNA isolation from plants, its structure, and the processes involved in DNA fingerprinting. It covers the essential components of DNA, including nucleotides and base pairing, as well as the importance of DNA in genetics. Demonstrations will be linked to understanding the molecular construction of DNA.