3.A.1
1. Discuss how Watson, Crick, Wilkins, and Franklin contributed to the
structure of DNA.
Watson & Crick:
created a three-dimensional model of DNA based on Wilkins’ and Franklin’s data
from their DNA X-rays.
Wilkins & Franklin: They worked on diffracting DNA with X-rays and discovered that DNA
is in the form of a double helix.
2. Discuss the Avery-MacLeod-McCarthy Experiments.
They proved that Griffith’s experiment with mice and two strains of
bacteria was the result of DNA transfer among the bacteria.
3. Discuss the Hershey-Chase Experiments.
They created an experiment that blended radioactive (yellow) proteins
into bacteria. And
The results of this experiment further proved
Avery, Macleod and McCarthy’s conclusion that DNA contains the information for
heredity.
4. Explain how genetic information is stored and passed on to
generations.
Genetic information is stored in something called chromatid. Chromatid
is a long dreand of genetic information called DNA, which is in the form of a
double helix. This is contained within a membrane inside most cells (all
eukaryotes) called the nucleus. If it isn’t in the nucleus, then it is just
hanging out in the cell (prokaryotes). When the cell is ready to divide, the
cell’s nucleus breaks down and the cell undergoes meiosis or mitosis, where the
cell can multiply its chromosomes and divide. Sometimes the chromosomes swap
pieces with other cells, called crossing over, and offspring are a genetic
combination of their parents. This increases genetic diversity within a
species.
5. Compare and contrast the DNA of eukaryotic and prokaryotic cells.
The DNA of eukaryotic cells is contained within a nucleus and have
multiple linear chromosomes. Prokaryotic organisms/cells have circular
chromosomes called plasmids. Sometimes bacteria have multiple plasmids and/or
linear plasmids and/or linear chromosomes.
6. What are plasmids?
Plasmids are round, double stranded molecules of DNA that CAN be found
in prokaryotes, eukaryotes and viruses, but not always. They are used in
genetically modifying organisms.
7. Explain the process of DNA replication. Use a drawing to help
explain.
8. Explain how retroviruses may have an alternate flow of information.
9. compare and contrast the structures of RNA and DNA.
Compare: Both have nucleotides, store genetic information, are in a
strand form, can be replicated, copied and contain a 5-carbon sugar, adenine,
cytosine, guanine and a phosphate.
Contrast:
DNA: in a double helix form, contains thymine, never leaves the
nucleus, duplicates during Meiosis/mitosis, is passed on to daughter cells.
RNA: Comes in three forms- mRNA, tRNA, rRNA. Single stranded, contains
uracil, can move inside and outside the nucleus, is temporary and copies DNA to
transfer to the ribosomes to make proteins.
10. Explain the process of Transcription. Use all enzymes involved and discuss the
lagging and leading strands.
11. Explain what happens to mRNA once it leave the nucleus.
It travels to a ribosome where tRNA translates and codes for amino acids which are then linked together to make specific proteins.
12. Discuss the process of translation. Include the essential
organelle and all the steps involved to create the protein.
13. Discuss translation in prokaryotic cells.
14. Discuss how the following can manipulate DNA: electrophoresis,
plasmid based transformation, restriction enzyme analysis of DNA, polymerase
chain reaction.
15. Discuss how each of the products of genetic engineering were
created: genetically modified foods, transgenic animals, cloned animals, human
insulin.
3.A.2
1. Explain the steps of the cell cycle. Mitosis Gl: where the cell
grows, DNA turns into chromatin and synthesizes mRNA and proteins. S phase: DNA
is duplicated and checked over for errors at the checkpoint. G2: rapid cell growth. Cytokinesis: the cytoplasm
and its contents are divided and the chromosomes are divided into two daughter
cells. In Meiosis this all happens again to produce four daughter cells.
2. Where are the checkpoints located and what do they do? They are
located at the end of G1, the end of G2 and the end of the M phase. These
checkpoints see if the cell is ready to divide and if the DNA is correctly
replicated.
3. Explain the purpose of the MPF factor.
It’s a protein made of cyclin-dependent kinase and cyclin. It allows
the cell to go into mitosis ONLY after the G2 checkpoint once the MPF
accumulates past a certain amount.
4. Explain how the PDGF signals the cell cycle.
It keeps the cell from growing when no cell growth is needed. IT
obtains signals from other cells or the environment and tells the cell if it
needs to grow/multiply or not.
5. Explain how cancer occurs to a cell.
Cancer occurs when the cell cycle is disrupted and the cell reproduces
abnormally fast, creating a mass of cancerous cells that must be surgically
removed or burned/frozen off.
6. Discuss how cyclin and cyclin dependent kinases control the cell
cycle.
These catalysts rise as the cell nears each check point. If the stuff
rises past a certain point at the check point, then the cell will move on to
the next phase of the cell cycle. If not, then the cell will repeat that phase
until it is deemed ready to progress.
7. Explain the relationship between mitosis and interphase.
They are linked and mitosis alternates with
interphase in the cell cycle. The interphase cycle pretty much prepares the
cell to replicate in mitosis.
8. Discuss the key points of mitosis.
Mitosis is the process in which the cell’s nucleus divides. It
consists of three major stages in interphase when the cell itself is not
dividing- G1, where the cell grows and functions normally, the S phase, where
the DNA is replicated and G2 is where the cell continues to grow and prepare
for mitosis.
9. Discuss the key points of meiosis.
Meiosis 1: Where the cell divides the first time into two daughter
cells.
Prophase 1: nuclear membrane breaks down and chromosomes become
visible. Spindle fibers begin to extend and chromosomes pair up and cross over.
Metaphase: Crossing over is complete and spindle fibers pull one of
each two chromosomes in each direction.
Anaphase: Cell begins to lengthen and the spindle fiber pulls the
chromosomes all the way to the microtubules. Chromosomes are complete, diploid.
Telophase: the cell begins to split off into two daughter cells, each
with a single complete set of chromosomes.
Cytokinesis: Cytoplasm undergoes cytokinesis, which replicates the
organelles and cytoplasm before and as the cell splits into two daughter cells.
Meiosis 2: There are now two
daughter cells.
Prophase 2: The spindle fibers replicate.
Metaphase 2: The chromosomes are moved to the center of the cells
(metaphase plate) by the spindle fibers. Each half of the kinetochores in each
of the chromosomes is bound to an opposite centromere.
Anaphase 2: The centromeres split the complete sister chromosomes and
begin to pull them to their centromere poles.
Telophase 2: The centromeres are pulled to the poles, the nuclear
envelope reforms and the two daughter cells split into four haploid daughter
cells.
10. Discuss how meiosis creates genetic variation.
In meiosis, which is the replication of sex cells, the two parent
cells’ chromosomes swap parts (pieces of the chromosome). This is called
crossing over and mixes the parent cells’ information to create a new,
genetically different cell.
3.A.3
1. Explain the rule of multiplication and addition.
You multiply and divide numbers before you add and subtract.
2. Explain the law of segregation.
Each parent contributes one of two alleles to its offspring so it
produces a pair of alleles.
3. Explain the law of independent assortment.
Each pair of alleles segregates independently from other pairs during
gamete formation. Like, they naturally pair up based on the gene each
chromosome codes for or whatever.
4. How does segregation and independent assortment result in genetic variation.
They allow the pairs of chromosomes to match up and switch parts
(cross over).
5. Give an example of a genetic disorder and explain the disorder.
Sickle cell anemia occurs when someone has two copies of the sickle cell
gene. The sickle cell gene causes blood cells to take on a crescent moon
(sickle) cell shape, which inhibits the cell’s ability to transfer oxygen and
move around the body.
6. Give an example of a chromosomal disorder and explain the disorder.
Down syndrome or trisomy 21 occurs when there is a third piece of
chromosome 21 in the DNA. It causes mental problems, odd facial features and
other health problems.
7. Explain nondisjunction.
Nondisjunction is when the chromosome doesn’t separate in half correctly
during meiosis. Missing, extra and even complete chromosomes are sent to the
daughter cells instead of the complete halves.
8. Explain why there are ethical, social and medical issues
surrounding human genetic disorders?
Well, if you know you have a genetic problem then it could make it
harder for you to find a lover, get health insurance, live life to the fullest,
etc. You would also have to live with knowing any children you may have could
inherit the genetic roblem.
3.A.4
1. Explain why Mendel’s laws do not apply to all traits.
Not all traits are dominant and recessive for one gene. At times there
are co-dominant, where both or more genes mix together and express in a mixed
way and incomplete dominant, where genes for a trait show at one time in
patches like black and white cows.
2. What are sex-linked traits?
Sex linked traits are traits that typically only show on male or
female genes. An example is the trait for color blindness which is only on the
X chromosome. They can also be expressed differently or not expressed based on
gender.
3. What is
nonnuclear inheritance? Give an example for plants and one for animals.
Mitochondrial DNA (animal & plant) and chloroplasts
(plant only) contain their own DNA (mtDNA and cpDNA). They are randomly given
to the gamete.
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