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Right answer is (b) False

To elaborate: PLASMODESMATA and GAP junctions are similar in function but they have difference in their structures. Gap junctions helps substance PASS through the cell membranes while the plasmodesmata FORMS a connection between the TWO cells.

Right choice is (a) CHORDATES

For explanation: Tight JUNCTIONS are present only in vertebrates, OTHERWISE known as chordates. The INVERTEBRATES CONTAIN a junction called septate junction.

Correct choice is (a) C28H39N7O9

Easy explanation: Rotigaptide has a chemical formula of C28H39N7O9 which is SHORTLY known as ZP-123. This is a drug which is now USED to treat ATRIAL FIBRILLATION. This drug has SHOWN to increase the conductance of gap junctions in cardiac muscle cells.

Right option is (b) Carvajal SYNDROME

To EXPLAIN: Carvajal syndrome is a GENETIC disorder CAUSED by both autosomal recessive and dominant gene. The disease makes the palms and soles’ SKIN thickened.

Correct answer is (B) USHER syndrome

Easy EXPLANATION: Usher syndrome is an autosomal recessive genetic disorder CAUSED by mutation. In this disorder the cadherin 23 is responsible for the deafness.

The correct answer is (b) 70-110

For explanation: The immunoglobulin MOLECULES have 70-100 amino acids, which VARIES according to the functions they are involved in our body. The number of amino acids ALSO depends UPON their size.

Right choice is (c) NERVOUS system

The explanation is: Protocadherins are abundant in the nervous system. They are PRESENT in neurons of our nervous system. A CERTAIN gene is present here to EXPRESS the protocadherin protein.

Correct answer is (a) MYCOPLASMA pneumoniae

The EXPLANATION is: Mycoplasma is a genus of bacteria that does not have a distinct cell wall over their cell membrane. Even though these bacteria LACK cell wall, they can effectively protect themselves against antibiotics which have a MODE of ACTION of inhibiting cell wall synthesis.

Correct choice is (B) Protozoa

The best I can EXPLAIN: The ANIMAL cells and the protozoa lacks cell WALL. They only contain cell MEMBRANE followed by the cytoplasm. Because of this they do not have a rigid shape.

The correct choice is (d) Homoserine lactones

Best explanation: Homoserine lactones are the signaling molecules a BACTERIA USES in cell-cell interactions. These HELP in their growth and metabolism.

Correct option is (a) Karl Rudolphi

The explanation is: Robert HOOKE in the year 1665 observed a component of cell CALLED the “wall” which SURROUNDS the cell. Karl Rudolphi and JHF Link found the component INDEPENDENT cell wall in the year 1804.

Right answer is (B) Brain ischemia

The EXPLANATION is: Brain ischemia, otherwise known cerebral ischemia where the BLOOD flow to the brain is constricted. The gap junctions are unable to provide oxygen thus the brain UNDERGOES hypoxia. This situation is permanent if it is untreated for prolonged TIME.

Correct answer is (a) Loss of ADHESION and GAIN of migration

Easy explanation: Epithelial mesenchymal transition is the property of CELLS losing adhesion and GAINING migration. It is highly useful in the pluripotency of stem cells in organ development.

Right choice is (C) Chitin

To ELABORATE: The FUNGI have a cell wall made of chitin, which is a glycosamine POLYMER. Chitin has similar functions with the PROTEIN keratin. It is structurally similar to the polysaccharide cellulose.

Correct OPTION is (B) Coagulation

The explanation is: Coagulation happens when the BLOOD platelets interact with the damaged TISSUE. It RELEASES a chemical signal for the other platelets to do the process of coagulation.

The correct ANSWER is (b) False

Easiest explanation: TIGHT junctions are made up of four different PROTEIN complexes NAMELY occludin, claudin, junctional adhesional molecule and tricellulins. These molecules being heterophilic in nature, they help in REGULATING the transport.

The CORRECT answer is (c) Epithelial cells

Explanation: The cell junction is ABUNDANT in epithelial cells, which provide barrier and CONTROL over the TRANSPORT in the cell. It is otherwise KNOWN as intercellular bridge, which is made up of multiprotein complexes.

The correct answer is (a) Zonula occludens – 1

To elaborate: Zonula occludens – 1 was the first TIGHT JUNCTION protein discovered in the year 1986, which is abbreviated as ZO-1. This has a molecular weight of 220kDa.

Right CHOICE is (a) True

Easy EXPLANATION: The bacteria are divided into gram positive and negative bacteria based on the thickness of the PEPTIDOGLYCAN present in their cell wall. The THICK peptidoglycan LAYER is gram-positive cell wall and thin layer of peptidoglycan is gram-negative cell wall.

Correct ANSWER is (b) 30-100 nm

The BEST explanation: The adherens JUNCTION is made up of several NUMBER of proteins. These adherens junctions have a size range from 30-100nm. They occur in epithelial and ENDOTHELIAL tissues.

Correct choice is (C) 1.2 – 2 nm

For explanation: The GAP junctions have a wide diameter of about 1.2 – 2 nm. These gap junctions are CAPABLE of ALLOWING molecules that are slightly larger than the normal sized ones.

Right OPTION is (b) 4 Å

Explanation: The RADIUS of the tight junction depends on the permeability of the materials which has to PASS through it. The claudin based pores have a radius of 4 Å. This may vary with DIFFERENT types of proteins.

The CORRECT option is (c) Biogenic silica

The explanation: The CELL walls of marine diatoms have biogenic silica which is otherwise known as biogenic opal. This is FOUND as small scales, granules or other geometric structures on the cell wall. This biogenic silica is a major contribution to the global carbon CYCLE.

Correct answer is (a) SEPARATION of FLUIDS

For EXPLANATION: The TIGHT junction is made up of multi-protein complexes, which helps in regulating the transport mechanism. In epithelial CELLS, the tight junction is useful in separating the extracellular fluids.

Correct CHOICE is (c) CARDIAC tissues

For explanation I would say: The DESMOSOMES are FOUND abundant in the cardiac, gastrointestinal and epithelial tissues. These desmosomes are found in the cells with more mechanical stress and has a stronger CELL to cell adhesion.

Correct answer is (B) Pseudomurein

The best I can explain: Pseudomurein otherwise known as PSEUDOPEPTIDOGLYCAN is ONE of the cell wall components of archaea BACTERIA. They resemble peptidoglycan layer in function and structure but differ in chemical composition. Lysozyme is a DEFENSE mechanism in higher animals and they cannot defend against bacteria containing pseudomurein cell wall.

Correct choice is (a) Giulio Bizzozero

The EXPLANATION: Desmosomes were discovered by Giulio Bizzozero from the epidermal LAYER, stratum spinosum. He was named as “a life SENATOR” by King HUMBERT I, for all his scientific ACHIEVEMENTS. He named them “nodes of Bizzozero”.

Correct answer is (d) PLACENTA

The EXPLANATION: The CDH3 gene CODES for P-cadherin PROTEIN that is found in the placenta where it acts as a cellular ADHESION molecule. Mutation of this gene has also been linked to many types of cancer.

Correct ANSWER is (a) Vohwinkel’s syndrome

The BEST I can explain: Vohwinkel’s syndrome is a skin disease caused by a disorder in the gap junction. It is characterized by THICK calluses in the PALMS of hands and foot. This disease is seen in the infant STAGES or early childhood.

Correct ANSWER is (c) 1000

Best EXPLANATION: The plant cells have around 1000 plasmodesmata, which connects them with the neighboring cells. These plasmodesmata serves as a channel, which helps the TRANSFER of materials from one cell to another.

The correct choice is (a) Strasburger

For explanation: Plasmodesmata serves as a connective system between TWO plant cells and in some algal cells. These were FIRST discovered by Strasburger in 1901. The discovery was aided by electron microscopic STUDIES.

Correct choice is (d) DESMOSOMES

Explanation: Desmosomes are otherwise known as macula ADHAERENS. This WORD is derived from the Latin LANGUAGE meaning ADHERING spot.

Right answer is (c) JOSEF Schaffer

The explanation: Josef Schaffer in the year 1920, coined the TERM “Desmosomes”. He got the WORD desmos from Latin, meaning binding and somes which MEANS body.

Correct option is (C) Cardiomyopathy

The best explanation: The arrhythmogenic RIGHT ventricular cardiomyopathy is caused by the mutations in the DESMOSOMES. This disease COMMONLY affects most of the young male atheletes.

Correct option is (b) Diffusion of drugs

The best I can explain: The TIGHT junctions take CARE of the permeability of the molecules through the CELLS. THUS the tight junction is RESPONSIBLE for the diffusion of the drugs through the cells.

The correct ANSWER is (a) Movement of leukocytes to tissues

The explanation: Leukocytes travel to tissues from CIRCULATION by moving past the cellular junctions. This PROCESS is known as extravasation and it OCCURS by interaction of cellular selectins and integrins.

The CORRECT option is (a) True

To explain: CADHERINS CONTAIN around 720 to 750 amino acid molecules. These amino acids are SYNTHESIZED by the posttranslational modifications made to the polypeptide chain.

The correct choice is (B) Actin

For explanation: The BASIC mechanism of adherens junction is that its cytoplasmic side should join with the actin FILAMENTS. The cadherins and catenin protein complex attaches itself to the actin filaments.

Correct answer is (c) Annular Shell

For EXPLANATION I would say: Annular LIPID SHELLS are complex formed by lipid molecules and membrane protein forming a continuous channel for TRANSFER for cellular molecules ACROSS different cells. These transmembrane channels are useful in importing/exporting lipids across the membrane.

The correct option is (a) Ca^2+

The BEST I can EXPLAIN: The CADHERINS is also known as calcium-dependent adhesion molecule. They require calcium IONS for its transmembrane FUNCTION.

The CORRECT choice is (a) IGG

Explanation: IgG is the most commonly FOUND immunoglobulin in the serum of humans. It is passed to the FETUS from MOTHER through the placenta. It has two antigen binding sites.