Biology

Question 3: (2 points) The famous scientist Johnny Nerdelbaum Frink decides to investigate a fly with unusual wings. He crosses a male fly with brown eyes and square wings to a female fly that has red eyes and square wings. The offspring consist of the following: 51 red, square 53 brown, square 18 red, oval 16 brown, oval Knowing nothing else about these flies, what could Frink deduce about the genotypes of the parents?

EXPERT ANSWER in this case, the parental phenotypes are- brown eyes, square wings, and red eyes and square wings. The number of parental types in the given progeny is much higher than that of the recombinants. So, Recombination frequency = (Number of recombinants / Total progeny) x 100% = (18 + 16 / 138) x 100% …

Question 3: (2 points) The famous scientist Johnny Nerdelbaum Frink decides to investigate a fly with unusual wings. He crosses a male fly with brown eyes and square wings to a female fly that has red eyes and square wings. The offspring consist of the following: 51 red, square 53 brown, square 18 red, oval 16 brown, oval Knowing nothing else about these flies, what could Frink deduce about the genotypes of the parents? Read More »

To help cope with the social distancing measures put in place in flattening the curve of COVID-19 infections, the healthcare industry had to adapt quickly to overcome it. Telehealth became a tool or medium for hospitals, clinics and doctors as one of the ways to provide the same quality of care services while minimizing the spread of the coronavirus infection. Telehealth is the use of digital information and communication technologies, such as computers and mobile devices, to deliver healthcare services to patients without the need to be in the same physical location.

QUESTION 1 To help cope with the social distancing measures put in place in flattening the curve of COVID-19 infections, the healthcare industry had to adapt quickly to overcome it. Telehealth became a tool or medium for hospitals, clinics and doctors as one of the ways to provide the same quality of care services while …

To help cope with the social distancing measures put in place in flattening the curve of COVID-19 infections, the healthcare industry had to adapt quickly to overcome it. Telehealth became a tool or medium for hospitals, clinics and doctors as one of the ways to provide the same quality of care services while minimizing the spread of the coronavirus infection. Telehealth is the use of digital information and communication technologies, such as computers and mobile devices, to deliver healthcare services to patients without the need to be in the same physical location. Read More »

If the ease of oxygen pick-up depends on oxygen concentration, would respiration be easier in air or in water?

EXPERT ANSWER Air consists of more free oxygen as compared to water (which consist of bound oxygen to water molecule). Also, in the air, the amount of oxygen is more as compared to water. Thus, if the oxygen pick-up would have depend upon the amount of oxygen, then the person would have been able to …

If the ease of oxygen pick-up depends on oxygen concentration, would respiration be easier in air or in water? Read More »

QUESTION 5. Below are two examples of colorectal cancer early lesions. Based on our discussion during the practical class, identify which image has the lesions with the HIGHER grade. Both cancers have genetic and genomic features typical of Consensus Molecular Subtype 1 (CMS1) of colorectal cancer. What are the genetic features of CSM1?

EXPERT ANSWER QUESTION 5 ANSWER: Image B has lesions with a higher grade. EXPLANATION: Image A shows low-grade lesions of colorectal carcinoma. Colon tumours that are poorly differentiated (high-grade) develop and spread more quickly than those that are well and moderately differentiated. HSIL aberrant squamous cells are darker and bigger than normal squamous cells when …

QUESTION 5. Below are two examples of colorectal cancer early lesions. Based on our discussion during the practical class, identify which image has the lesions with the HIGHER grade. Both cancers have genetic and genomic features typical of Consensus Molecular Subtype 1 (CMS1) of colorectal cancer. What are the genetic features of CSM1? Read More »

1. Beta-catenin is a core component of the cadherin protein complex, which plays a very crucial in the wnt-signaling pathway. In the absence of the wnt-signal, the Beta-catenin was mutated so that its phosphorylation is inhibited. What changes in the wnt-signaling pathway can be observed, under above conditions? What can be observed, if the TCF undergoes mutation causing it to be unable to bind to the transcription co-repressor (Groucho), in the absence of beta-catenin? Is beta-catenin capable of regulating the wnt gene expression process once TCF and the co-repressor (Groucho) are separated from the cell?

EXPERT ANSWER In animals, wnt family members are widely conserved since they are required during growth, tissue patterning, and homeostasis because the canonical wnt signaling pathway controls cell fate by regulating gene expression. This signaling pathway starts by binding to the Frizzled and LRP5/6 coreceptors leading to the formation of a nuclear transcription complex that …

1. Beta-catenin is a core component of the cadherin protein complex, which plays a very crucial in the wnt-signaling pathway. In the absence of the wnt-signal, the Beta-catenin was mutated so that its phosphorylation is inhibited. What changes in the wnt-signaling pathway can be observed, under above conditions? What can be observed, if the TCF undergoes mutation causing it to be unable to bind to the transcription co-repressor (Groucho), in the absence of beta-catenin? Is beta-catenin capable of regulating the wnt gene expression process once TCF and the co-repressor (Groucho) are separated from the cell? Read More »

QUESTION 3. Describe the characteristics of the beta-catenin staining in the tumour tissue below and its implication with regard to the wnt signalling pathway.

EXPERT ANSWER Besides, β-catenin promotes the progression of tumors via suppressing the T-cell responses . The activity of β-catenin is controlled by a large number of binding partners that affect its stability, cellular localization and transcriptional activity. In the canonical Wnt cascade, β-catenin is the key effector responsible for transduction of the signal to the …

QUESTION 3. Describe the characteristics of the beta-catenin staining in the tumour tissue below and its implication with regard to the wnt signalling pathway. Read More »

A genetic disease causing poor resistance to bacterial infection is linked to an unknown mutation in a gene carried by the X chromosome. The cDNA corresponding to this gene is used as a radioactive probe for Southern blot and Northern blot analyses. The results of these 3 experiments are illustrated below.

Figure: Diagram representing the position (and size) of the DNA fragments (Southern blot, left panel) and RNA transcripts (Northern blot, middle panel) recognized by the radioactive probe. The range of size listed on the left side of the left panel applies only to the Southern blot. The size of the proteins coded by the wild …

A genetic disease causing poor resistance to bacterial infection is linked to an unknown mutation in a gene carried by the X chromosome. The cDNA corresponding to this gene is used as a radioactive probe for Southern blot and Northern blot analyses. The results of these 3 experiments are illustrated below. Read More »

This is the result of the Western blot experiment. Explain the different signals in different lanes in the western blot results. Why did the horse serum give the weakest signal?

These antibodies were used: Rabbit anti-rat serum primary antibody binding Goat anti-rabbit IgG conjugated with alkaline phosphatase (AP) as secondary antibody EXPERT ANSWER As per mentioned experiments, have to write different molecular weight of protein marker. In lane 2, lane 3, lane 4, lane 5, lane 7, lane 8, lane 9 the molecular weight of the given …

This is the result of the Western blot experiment. Explain the different signals in different lanes in the western blot results. Why did the horse serum give the weakest signal? Read More »

name the various cell components involved with protein synthesis. How does each participate?

EXPERT ANSWER Answer : Various cell components involved in protein synthesis : Nucleus → Ribosome → Endoplasmic Reticulum → Golgi Apparatus. 1. Nucleus: Gene Transcription (DNA to messenger RNA (mRNA)). 2. Ribosome: mRNA translated to a polypeptide (for proteins staying in the cell, this is the last stop. For proteins to be secreted out of …

name the various cell components involved with protein synthesis. How does each participate? Read More »