DNA, RNA, Proteins synthesis Homework #1: The basic of DNA
What does DNA stand for?
deoxyribonucleic acid
If 20% of the nucleotide in a DNA molecule are adenine, what percentage of each of the other three bases would be found in this molecule. This is known as _______ rule.
each compose 30% ; chargaff's rules
What are the sides of DNA ladder made of?
sugar and phosphate
What are the rungs of the DNA ladder made of?
nitrogen bases
A beadlike structure formed of several histones with corresponding DNA; they pack closely together to super coil the DNA.
nucleosomes
what 3 critical things be able to do
-Genes must be able to store and carry the genetic info -Genes must be able to put this info to work to produce the traits of organism -Must be a mechanism of copying this info so that new cells have a complete set of the genetic info
Pyrimidine
1 ring in structure (thymine and cytosine)
Purine
2 rings in structure (adenine and guanine)
Deoxyribose
5 carbon sugar in DNA
Rosalind Franklin x-ray crystallography photographs provided what 3 clues about the structure of the DNA molecule
A) It showed that the strands in Dna were twisted around each other B) It showed that the Dna molecule were double stranded C) It showed that the nitrogen bases were located in the center of the molecule.
Using letter to symbolize the nitrogen bases, indicate which bases always pair together. How many bonds hold each pair?
Adenine bonds with thymine; two hydrogen bonds are formed between them Guanine bonds with cytosine; 3 hydrogen bonds form between them.
Name the four nitrogen bases found in DNA.
Adenine, Guanine, Thymine, Cytosine
If the nucleotide sequence on one side of the DNA molecule is GTCATG, what would be the sequence of bases complimentary to this?
CAGTAC
How did Chargff's rules help watson and crick develop their model of the DNA molecule?
Cytosine equal to the amount of guanine. Same for Adenine/guanine.
Which of the following would not be found in a nucleotide?
DNA Polymerase
Nucleosomes
DNA coiled around histones
Histones
DNA tightly coiled around proteins
How can an enormous amount of DNA fit inside one cell
DNA wrapped tightly around proteins called histones. DNA is wrapped twice around a group of 8 histones forming a bed like structure called a nucleosome. This forms a chromosomes.
Why did Watson and Crick refer to the DNA molecule as a "Double Helix"
Double refers to the fact that the molecule is doubled stranded or is composed of two sides. Helix refers to the spiraling nature of the molecule; the two sides are twisted around one another.
Inside the nucleus, the DNA is tightly wounded around proteins
Histones
The two sides of the DNA molecule are held together across the center of the helix by what type of bond?
Hydrogen Bonds
Which of the following doesn't describe the structure of DNA?
It contains the 5-carbon sugar, ribose
The chromosomes that are found in prokaryotes are different from those found in Eukaryotes. Which of the following describes prokaryotic DNA?
It is a Single, circular chromosome
What is the function of DNA in Cells
It stores the information that directs the ribosome in protein synthesis.
What two men together discovered the structure of the DNA molecule?
James Watson and Francis crick
What is the name of the small repeating subunits that compose DNA and RNA?
Nucleotides
Ribose
RNA
This person's x-ray crystallography photographs provided the vital clues in solving the structure of DNA.
Rosalind Franklins
Define complimentary base pair and give example
The DNA nucleotides always pair in this way: adenine pairs with thymine and cytosine pairs with guanine.
What is the name of the structure seen to the right? Label 3 parts composing this structure. How are the three parts held together?
This is a drawing of a single nucleotide. The PO4 in the yellow circle is phosphate group.The green, 5-sided shape is sugar, deoxyribose. The orange, 6-sided shape is a nitrogen base. The sugar is held to the nitrogen base on one side and tot eh phosphate group on the other side by covalent bonds.