How do antibodies neutralize pathogens during

an infection?

This is an

open book graded quiz. The grading scheme for this quiz is the same as the previous

graded open-book quiz.

The goal of this graded quiz is to help you connect

biological concepts with real-world applications. In this quiz, we follow

Prerna, a student at Plaksha, as she discovers the connection between biology

and sports. She realizes that the biomolecule that helps keep her hydrated due

to homeostasis also plays a role in water treatment—an important aspect of the

grand challenge of ensuring water security.

Trial

question:

What is the main theme of the graded quiz?

Hopefully you had a good learning experience. Do you have any feedback/suggestions for improvement/or any other comments?

The

storyline following Prerna’s journey made the quiz more engaging and helped me

better understand the concepts.

Excited by this

discovery, Prerna realizes that recombinant DNA technology could provide a

scalable way to produce aquaporins for water filtration applications. By

inserting the gene encoding aquaporin into a bacterial plasmid, scientists

could harness microbial systems to synthesize the protein efficiently. This

approach could be a crucial step in taking inspiration from nature to engineer

biological systems that help combat water pollution and provide clean water.

On this World Water

Day, let’s take a moment to reflect on the challenges in the water sector and

acknowledge our role in being part of the solution. Even small actions—like

preventing water wastage from our taps—can make a difference!

The answers to

followings questions will not affect your grades, but will give us a feedback

on what can be improved with such quizzes.

a) Relevance of Biology to Engineering

Central Dogma – From Genes to Proteins

As

Prerna continues reading about aquaporin-based membranes, she learns that one

of the key challenges companies face is the mass production of aquaporins.

Synthesizing such a complex protein purely through abiotic methods (using purely

physio-chemical processes) is extremely difficult due to its intricate

structure.

Drawing

on her knowledge of the central dogma of molecular biology, Prerna wonders

whether aquaporins could be produced using recombinant DNA technology. She

researches further and discovers that this approach is indeed feasible. The

following figure shows a simple schematic of recombinant DNA technology, and

the bottom figure shows some key amino acids present in the aquaporin protein

(also consider the amino acids present in the NPA motifs, and the amino acids H,G

and R).

She comes across a study that is designing a recombinant plasmid to express an aquaporin protein.

They want to insert a 15-nucleotide-long

gene sequence that encodes for a critical segment of the aquaporin

transmembrane domain. Based on the amino acids found in aquaporin (as shown in

the image), choose the correct answers with respect to recombinant DNA

technology and which of the following DNA

sequences is the most ideal choice? (Assume that the DNA strand is the

coding strand).

Nature inspired design

She tried to understand how

aquaporins are used in synthetic membranes. The following image presents a

schematic of such a membrane, illustrating how aquaporins are embedded within a

single membrane sheet. As the feed solution passes through the membrane,

aquaporins facilitate selective water transport, resulting in the production of

clean water. Which of the following statements correctly describe the role of

aquaporin-based nanomembrane filtration in water purification?

When Prerna learned

about the crucial role of aquaporins in water transport, she wondered if they

could be applied to water purification and treatment systems. Their high

selectivity seemed to offer advantages over conventional filtration methods.

Curious, she searched online and discovered that synthetic membranes

incorporating aquaporins are actively being developed for water treatment. In

fact, she came across reports suggesting that aquaporin-based membranes can

reduce energy consumption significantly compared to traditional filtration

systems.

Practice question: What potential advantage do aquaporin-based

membranes offer in water treatment?

Importance of channel proteins for water transport

Since aquaporins are essential

for water transport across cells, they are widely distributed throughout the

body in tissues where water movement is critical. Different types of aquaporin

proteins, such as Aquaporin 1 (AQP1), Aquaporin 6 (AQP6), and Aquaporin 10

(AQP10), each serve distinct functions.

In the kidneys, the hormone

antidiuretic hormone (ADH) regulates water reabsorption by controlling the

expression and activity of aquaporins, particularly in the collecting ducts.

Based on the information

provided in the images, which of the following statements accurately describe

the role of aquaporins in physiological processes and their involvement in

water balance regulation?

Structure function relationship

The

image illustrates the structure and function of aquaporins, membrane proteins

that facilitate water transport across cell membranes. On the left, a

simplified representation depicts water molecules passing through an aquaporin

channel. On the right, a detailed view shows the aquaporin structure: the top

part displays the linear polypeptide with NPA motifs

(asparagine-proline-alanine), while the bottom part presents the folded,

functional form. Choose the correct answers: