Final Exam Biology

one parent is homozygous and the other is heterozygous)

50% carrier 50% inherit

Social unrest in West Africa, where Sickle cell anemia is most common, is forcing people to migrate to other countries. Which population genetics phenomenon is driven by migration?

Gene flow

What type of mutation causes Huntingtons Disease?

HTT mutation

Steroid hormones, such as estrogen & testosterone, are derived from cholesterol. What type of macromolecule are they?

Lipids

Some people think that you lose weight as heat or as sweat, explain why this is wrong even though we produce do heat and sweat with exercise.

Mass leaves from the CO2 we exhale. The glucose we consume gets broken down and eventually ends with CO2, which we exhale.

What if you were designing an energy drink exclusively for high altitude mountain climbers, which component would you add the most? NAD+, NADH, Pyruvate, Acetyl-coA, CO2. Explain why. What is the function of each of these components in cell respiration?

NAD+ accepts the electrons with high energy and carries them to make ETC where they used to synthesize ATP. NADH helps to oxidize in the cell processes such as glycolysis, which helps with oxidation of glucose. Pyruvate is used in the molecules and recycles. Acetyl-coA is produced in the second step of aerobic respiration after glycolysis works and works to carry carbons atoms to the TCA cycle so it can be oxidized for energy production. CO2 is given off as a waste product.

Huntington's disease affects individuals late into adulthood, after most individuals have already reproduced. Can Natural Selection shape traits that have an effect after reproductive age?

Natural selection can shape traits that have an effect after reproduction age with heterozygous allele

Do all mutations cause disease?

No

What would happen to a patient with Huntington's if you somehow manage to block the promoter region of the huntingtin gene?

No H disease would not be able to produce and CBP wouldn't be blocked. Normal cell production would occur

Can you copy the gene region in a human chromosome and insert it into a bacterium directly?

No, could be death in a organism since there is a difference in the DNA and chromosome

could this effect be produced in a prokaryote, why?

No, prokaryotes do not have a transcription factors

In the presence of huntingtin, are the genes activated by CBP expressed? Explain.

No, the genes are not getting activated by the CBP and not being expressed

Mountain climbers get in trouble when climbing at high altitude because there is less oxygen in the atmosphere as you go up in altitude. Would an energy drink help them improve their performance? Explain

No. There is a lack of oxygen, meaning there is no molecule that would act as a final electron carrier. They would perform lactic acid fermentation.

A small group of people moved to a new uninhabited territory and established the new Kingdom of Wakanda. Two of the individuals in this population develop a blue fluorescent glow when exposed to the metal vibranium, which is very abundant in Wakanda. Individuals from the opposite sex find this blue glow very attractive. Which deviations from Hardy-Weinberg Equilibrium are taking place in this population?

Non-random mating and gene flow

What would happen if you add 3 new nucleotides to a gene?

Nothing, it is read in 3's

Which step in gene expression would be the most promising to change in order to produce a normal version of the huntingtin protein despite having the allele with the mutation.(Huntington)

Transcription with transcriptional dysregulation

Is SCA mutations the result of a mistake in DNA replication or transcription

Transcription, the amino acid chain became altered

Some steroid hormones stimulate tissue growth, such as estrogen's effect on breast tissue. Which type of cell division is being activated?

mitosis

What would be the phenotype of a heterozygous person?

1 dominant 1 recessive

If you were to design your own energy drink, which of the following components would you add (assuming none of these gets degraded during digestion): NAD+, NADH, Pyruvate, Acetyl-coA, CO2. Your answer will be different depending on how you are judging it: 1) which one has the most energy per carbon, 2) which one would make the most ATP per molecule, and 3) which one would require the least number of steps to make ATP. Explain why.

1. Pyruvate has the most energy because it has 3 carbons 2. CO2 3. Acetyl-coA

If the father has the disease but the mother doesn't have the disease, what are the chances that the offspring will inherit these diseases? (assume both parents are homozygous,

100%

During puberty, the production of steroid hormones in the gonads rises and it is released into the blood stream. What is the concentration gradient of the blood in comparison to other cells in the body? In which direction will testosterone move?

The concentration gradient of blood compared to other cells is 10x higher. It uses facilitated diffusion and moves into the cells.

Let's say that Robert Baratheon, despite being king, was unlucky enough to be heterozygous from Huntington's disease and heterozygous polycystic kidney disease-2 (caused by a mutation in the Polycystin-2 gene). Robert inherited both diseases from his father, his mother was healthy. Assuming the genes for Huntington's disease and polycystic kidney disease-2 are located close together on the same chromosome, and knowing he got both diseases from his father, what are the genotypes of the gametes that Robert can produce and would all be equally as common or would some be more common than others?

both genes are linked

You are developing a new vaccine for COVID-19. You are deciding what to include in the solution (liquid) along with the vaccine, which will be injected intravenously (directly into the veins). You don't want to harm the blood cells, so you know you need to use an isotonic solution to deliver the vaccine. What type of solution would you use (hypertonic, isotonic, hypotonic) and what types of solutes would you use?

An isotonic solution will stabilize

What is the heritability pattern of Huntingtons (dominant, recessive, incomplete dominance, etc)?

Autosomal recessive: both copies of genes have the mutation

What is the heritability pattern of SCA (dominant, recessive, incomplete dominance, etc)?

Autosomal recessive: both copies of genes have the mutation

Vaccines work by providing organisms to a brief exposure to an antigen, enough that the immune system generates a memory for future encounters but not too long to generate a full-blown immune reaction. What are the advantages of using RNA instead of DNA for vaccines? List and explain all the advantages based on your reading of the article and what you learned throughout the semester.

By using RNA instead of DNA vaccines, we are able to prevent anything happening to our natural DNA sequence. With the mRNA when it enters the cell, it gets translated into proteins which will help the bodies immune system

What is the effect of those SCA on the structure of the protein

Causes hemoglobin molecules to stick together and create irregular red blood cell shapes.

What is the effect of Huntington mutations on the structure of the protein

Causes the proteins to have abnormally long strings of a single amino acid.

Cancer cells divide very often. What happens to the chromosome of cells? How can they counter it? Can this also happen in prokaryotic cells?

Chromosomes shorten with every division, as the end of the chromosomes cannot be replicated. Cells use telomeres and primers to counter this. Prokaryotic cells have circular DNA and thus cannot do this.

What event in meiosis is the main source of genetic recombination in genes that are close together on the same chromosome?

Crossing over

Is Huntington present in the DNA RNA or both?

DNA because it involves DNA segments

Is SCA present in the DNA RNA or both?

DNA because the DNA makes instructions for the hemoglobin

We all derived from a single cell called a zygote, which resulted when a sperm cell fertilized an egg. Yet, we have many different types of cells that perform very different functions. How is this possible?

Different cells that are specialized only express certain genes that allows them to perform a special function

Birth control pills are mostly composed of estrogen and they have been linked to higher risk of breast cancer. Formulate the relationship between estrogen, cancer and the cell cycle.

Estrogen stimulates mitotic growth in breast tissue. Taking in estrogen that the body does not naturally produce may disrupt the homeostasis and result in missed checkpoints during mitosis. This could lead to tumors.

The mutation for Huntington's disease appears to have originated in Western Europe, with a prevalence of 7 in 100,000 people. However, an isolated population in Lake Maracaibo in Venezuela, of European descent, have an increased prevalence of 700 in 100,000. Which population genetics phenomenon could be responsible for this?

Founders effect

Sickle-cell anemia is caused by an abnormal hemoglobin molecule that changed the shape of red blood cells. This disease can lead to various health complications that are often lethal. However, heterozygous individuals have minor symptoms. Moreover, heterozygous individuals show an advantage with decreased vulnerability to Malaria. The allele for Sickle-cell anemia is most common in tropical areas where malaria is common. Which population genetics phenomenon could be responsible for this?

Heterozygous advantages

The protein produced by Huntington's disease (huntingtin) interferes with general transcription factor (called CBP) and prevents it from binding the promoter. CBP activates genes involved in cell survival. i) Which step in gene expression is huntingtin preventing?

Huntington is preventing the initiation stage

How do we lose weight? Where is the mass going?

Into CO2. We breath it out

We used the analogy of comparing a cell to a university, where the DNA is the collection of recipe books in the library, the RNA transcripts are the photocopies of specific chapters of those books, ribosomes are the cooks. In this analogy, what is each book equivalent to and what is each book chapter equivalent to?

It refers to DNA replication and its steps

What type of mutation causes Sickle Cell Anemia?

Point Mutation

Is Huntingtons mutations the result of a mistake in DNA replication or transcription

Replication, HTT is inherited

Given what you know about how Natural Selection works, explain why Sickle cell disease hasn't been eradicated from the population.

SC hasn't been eradicate because of Heterozygous advantages or balancing selections.

They often have long-term developmental effects, such as hair growth, muscle mass increases, sexual development, gamete production, etc. How can steroid hormones be responsible for these long-term effects?

Steroid hormones can alter gene expression so they can result in long term effects

Can steroid hormones cross the plasma membrane? What type of transport would they require?

Steroid hormones can cross the plasma membrane if they are free. They use passive diffusion

Sickle-cell disease is caused by a mutation in the hemoglobin gene located on chromosome 11. While Huntington's disease is caused by a mutation in the Huntingtin gene located on chromosome 4. What can you infer about the inheritance of these diseases? Are the genes for Huntington and Sickle cell anemia genetically linked? Would they satisfy Mendelian ratios? Explain

The genes would be inherited independently. It would satisfy the mendelian ratios because of this

What would happen to blood cells if a high solute (hypertonic) solution is injected intravenously? What if you use a hypotonic solution?

The hypertonic solution would cause water not to move out of the cells. This would cause the cells to crenate. A hypotonic solution would bring in water which would cause the cells to swell and burst

If instead of making an energy drink, you come up with an energy injection, how would that affect the ingredients you put into the shot? Think in terms of polarity and tonicity.

The ingredients in a injection are going to be more concentrated than in a drink. Tonicity can affect the drug absorption. Polarity can be determined if the substance will dissolve in the cell or not.

Some boxers and wrestlers dehydrate abruptly by spending time in a sauna and sweating a lot in order to lose weight and compete with a lower tier, however this is a serious health hazard, explain what happens to the tonicity of someone who does this.

The mass dehydration causes cells to shrivel. Cells crenate and cannot perform their function properly and eventually die off

One of Robert's brothers is colorblind (a sex-linked condition) and will not be able to become a warrior. Robert is not colorblind but he is worried that one of his kids may be colorblind just like Robert's brother. What are the chances of this happening? One of Robert's sons did turn out to be colorblind, how would you explain this?

The son would inherit it if the mom was heterozygous/homozygous for mutation as she would have passed it on from her X chromosome.

Where do you expect the receptors for steroid hormones to be located?

They are located in the cytoplasm

Why do we breathe? Which molecules do we breathe in, and what is the purpose? Which molecules do we breathe out, and where do they come from?

We breathe in order to make energy. We breathe in oxygen which gets used as a final electron accepter. We breathe out CO2 as waste product. The CO2 comes from the glucose molecule that was broken down from our food.

Energy drinks have two key ingredients, one is sugar, and they have lots of it! What we call sugar is the disaccharide sucrose, which is composed of glucose and fructose. The other component is some sort of metabolism stimulant, like caffeine. Do energy drinks really provide energy? If so, how do your cells get that energy from the drink? What if it's a sugar free energy drink?

Yes, they provide disaccharide which can be broken to glucose which can be used for energy. Metabolism stimulant, however, does not provide energy, merely gives a temporary since of energy and awakeness. If it is a sugar free drink, your body will store more calories as fat and use fewer calories for energy because you are changing the way you metabolize calories.

The latest COVID vaccines use mRNA, which is a large polar molecule. How can such molecule enter the cells? Why do mRNA vaccines use a lipid coat?

mRNA is translated by rRNA when it enters the nucleus envelope into cytoplasm. Lipids prevent cell division and serves as a layer for antibody

explain why are RNA vaccines faster to produce than other types of vaccines?

mRNA vaccines teach the human body to recognize the spikes and allows the body to produce antibodies to stop the virus before it forms. The components are easier to produce