S1p2 Flashcards
1.Belgian Blues have more, and large muscle cells than ordinary cattle because
lack of myostatin.
Belgian Blues cattle pre muscle cells
multiply more than normal
The name of the British researcher that tried to make a vaccine to prevent pneumonia was________________
Frederick Griffith
The two strains used in the development of the pneumonia experiment are :
Rand S
The following scientists concluded that transformation must be caused by DNA ,and not by traces of protein contaminating the DNA
Avery, Colin, Leod and Mc Carty.
All are characteristics of DNA EXCEPT
being single-stranded.
What are the complementary bases of a DNA double helix?
AT and CG.
Which scientists are credited with discovering the physical structure of DNA?
Watson and Crick.
Nucleotides of DNA are composed of three substances, named:
sugar, phosphate, and nitrogenous base.
What is the role of hydrogen bonds in the structure of DNA?
connect the base pairs.
This enzyme pulls apart the parental DNA double helix and is called
DNA helicase
The enzyme that moves along each separated parental DNA strand, matching bases on the parental strands with complementary free nucleotides is called
DNA polymerase
The scientists that made the first DNA X rays were
Franklin and Wilkins
The 5-carbon sugar in DNA is called
deoxiribose
If a nucleotide pair in a sequence is deleted the mutation is called
deletion.
The basic units of DNA are called:
nucleotides
Bases that can form pairs in DNA are called
complementary
c. The four nitrogenous bases in DNA are called:
adenine, guanine, thymine and cytosine
The sugar of one nucleotide is linked to:
the phosphate
Two nucleotide strands wind together to form a
double helix
a protein that is in all mammals is what makes the muscles not grow in an exaggerated way. It means “to make muscles stay the same”. is….
Myostatin:
Belgian Blue bulls have larger muscles than ordinary bulls. These because ?
they don’t produce normal myostatin.
How did scientists discover that genes are made of DNA?
Late 1800’s scientists knew genetic information existed in genes. – they didn’t know what a gene was.
1900’s studies of divided cells provided evidence that genes are part of chromosomes.
Antibacterial vaccines consist of:
- A weakened strain of the bacteria, it can’t cause illness. Injecting the weakened but living strain into an animal may cause immunity against the strains.
- Others use disease-causing (virulent) bacteria that has been killed by exposure to heat or chemicals.
who said tried to make a vaccine to prevent bacterial pneumonia?
Frederick Griffith
Griffith’s Experimented with 2 strains of the bacterium Streptococcus pneumoniae
- R-strain: didn’t cause pneumonia when injected.
- S-strain: when injected it did cause the illness and killed the mice in 2 days.
Who discovered that the transforming molecule is DNA
- Oswald Avery
- Colin MacLeod
- Maclyn McCarty
They insolated DNA from the live S-strain and mixed it with live ________ and produced live________.
R-strain, S-strain.
with DNA-destroying enzymes: it prevented the
transformation
DNA consists of long chains made of subunits called _________
nucleotides
nucleotides consists of 3 parts:
- Phosphate group
- Sugar called deoxyribose
- 1 of 4 nitrogen containing bases.
The bases of nucleotides are:
- Adenine (A)
- Thymine (T)
- Guanine (G)
- Cytosine (C)
who analyzed the amounts of the four bases in DNA from diverse organisms like bacteria, fish and humans?
Erwin Chargaff
Who used X-ray diffraction to study the DNA molecule. They bombarded crystals of purified DNA with X-rays and recorded how they bounced off the DNA?
Maurice Wilkins and Rosalind Franklin
Wilkins and Franklin could extract information about DNA from the pattern. Which information?
- It is long and thin - Uniform diameter of 2 nanometers
- It is helical, twisted like a spiral staircase.
- It is a double helix – 2 DNA strands coil around one another.
- Consists of repeating subunits
- Phosphates are outside of the helix.
Who combined the diffraction data with knowing how complex organic structures bond and considering that “important biological objects come in pairs”, deduced the structure of DNA?
James Watson and Francis Crick:
is bonded to the sugar of the next nucleotide, making a sugar-phosphate backbone of alternating covalently bonded sugars and phosphates. The bases stick out of the backbone.
The phosphate group of one nucleotide
Watson and Crick said that a complete DNA molecule consists of
- 2 strands of DNA assembled like a twisted ladder.
- The sugar-phosphate backbones form the uprights of the ladder.
- The rungs are specific pairs of bases, with one member of each pair coming from the backbone. The pair of bases are held together by hydrogen bonds.
- The 2 strands in the double helix are antiparallel to one another, they are oriented in different directions.
Complementary bases:
A-T
G-C
How does DNA replication ensure genetic constancy during cell division?
Rudolf Virchow said cells come from preexisting cells. Almost every cell in the body contains identical genetic information that is the same from when we are a fertilized egg.
Essential ingredients for replication:
- Parental DNA strands
- Free nucleotides
- Enzymes that unwind the parental DNA doble helix and synthesize new strands.
the ones that break the doble helix. They pull apart the parental doble helix, so the bases no longer form base pairs with each other is:
DNA helicase:
enzyme that synthesizes a DNA polymer. They move along separated parental DNA strand, matching bases on the parental strands with complementary free nucleotides is:
DNA polymerase:
What are mutations and how do they occur?
The nucleotide sequence is preserved with great precision.
what is mutation?
occasional changes in the nucleotide sequence. / An alteration in sequences of DNA
rare causes of mutations are:
- X-rays
- UV rays
- Some cigarette components
- Some fungi
Types of mutations?
- Inversion
- Translocation
- Insertion
- Deletion
- Point mutation or substitution
