Test di Medicina 2020 Worked Solution

Full explanation

The Lord of the Rings was written by J.R.R. Tolkien and published in three volumes between 1954–1955.

It is one of the best-selling novels ever written, with over 150 million copies sold.

Other options B. J.K. Rowling — author of the Harry Potter series C. C.S. Lewis — author of The Chronicles of Narnia (a close contemporary and friend of Tolkien's) D. Vladimir Nabokov — Russian-American author known for Lolita and Pale Fire E. Isaac Asimov — prolific science fiction author known for the Foundation series and I, Robot

Full explanation

Beyond Good and Evil was written by Friedrich Nietzsche, published in 1886 — not Freud.

Other options A. The Interpretation of Dreams (1899) — One of Freud's most famous works; introduced his theory of the unconscious through dream analysis C. Totem and Taboo (1913) — Freud applied psychoanalytic theory to anthropology and the origins of religion and morality D. The Ego and the Id (1923) — Introduced Freud's structural model of the psyche: id, ego, and superego E. On Narcissism: An Introduction (1914) — Foundational paper introducing the concept of narcissism into psychoanalytic theory

Full explanation

A mercenary is a soldier who fights for personal financial gain rather than for ideological, national, or patriotic reasons — serving any employer willing to pay.

Other options A. Conspirator — Someone who takes part in a secret plot or conspiracy; no military-for-hire connotation B. Assassin — Someone who murders a prominent person, typically for political reasons; not necessarily a soldier-for-hire C. Janissary — Elite infantry units that formed the Ottoman Sultan's household troops and bodyguards; they were conscripted (often as children) — not voluntary mercenaries E. Plotter — A person who secretly plans something harmful; similar to conspirator, purely civilian in connotation

Full explanation

Article 76 of the Italian Constitution governs delega legislativa — the mechanism by which Parliament can delegate its legislative function to the Government (via decreti legislativi), provided guiding principles, criteria, time limits, and defined purposes are set.

Explanation of each option Government — Correct.

Legislative power belongs to Parliament, but Article 76 allows it to be delegated to the Government under strict conditions (principles, criteria, time limit, subject matter).

This is the constitutional basis for decreti legislativi.

President of the Republic — The President promulgates laws and issues decrees (e.g., decreti del Presidente della Repubblica), but is not the body to which Parliament delegates legislative function under Art. 76.

The President's role here is formal/signing, not legislative delegation.

High Council of the Judiciary (CSM) — The CSM is the self-governing body of the judiciary (Art. 104), handling judicial appointments/discipline.

It has no legislative role at all.

Prime Minister — The delegation goes to the Government as a collective body (Council of Ministers), not personally to the Prime Minister.

Minister of Justice — A single ministry has no independent legislative delegation power; legislative decrees are adopted by the Council of Ministers as a whole.

Full explanation

Even if some of the words are not the most common ones we see every day, since rough and smooth are words we use all the time, we can easily guess the correct answer.

"rough" and "smooth" describe opposite textures/qualities.

Mirage – Fata Morgana are synonyms — Fata Morgana is actually a specific (and dramatic) type of mirage/optical illusion, often used interchangeably with "mirage" in general usage.

Clear – Silvery are synonyms — in a descriptive/poetic sense, both can describe something bright, pure, or clear (e.g., a "silvery" voice or light is also "clear").

Strait – Channel are synonyms — both refer to a narrow body of water connecting two larger areas.

Strong – Bastion are synonyms — as nouns, both can refer to a fortified stronghold or defensive structure (a "bastion" is a type of fortification, and "a strong" historically meant a fortress).

Full explanation

Hippocrates of Kos (c. 460–370 BC) is traditionally regarded as the father/founder of scientific medicine, for moving medicine away from superstition and divine causation toward observation, clinical reasoning, and natural explanations of disease.

Leucippus — A pre-Socratic philosopher, co-founder (with Democritus) of atomism, not medicine.

Epicurus — Founder of Epicureanism, a philosophical/ethical school focused on pleasure and atomistic physics, not medicine.

Aesculapius (Asclepius) — The mythological Greek god of healing, not a historical figure; medicine in early Greece was tied to his cult (temples called Asclepeia), representing the pre-scientific, religious approach to healing that Hippocrates moved away from.

Pericles — Athenian statesman and leader during Greece's "Golden Age," unrelated to medicine.

Full explanation

To tackle these time zone questions, it’s helpful to have a basic understanding of the geography of cities and countries.

Memorizing the time zones of 5-6 major cities can also be a great starting point.

Most European countries observe UTC+2 during the summer and UTC+1 during the winter.

Recommended time zone list to memorize

In 19:00 (7 p.m.) on 4 September 2020 in Rome,

A) Seoul Relate to my Tokyo/Seoul anchor: UTC+9.

Difference from Rome: +9 − 2 = +7h 19:00 + 7h = 02:00 next day → 5 September

B) Baku (Azerbaijan) Not on the list, but if we relate it geographically, Baku sits closer to Dubai than to Mumbai.

So, if we think with the Dubai time zone, the difference from Rome = 4 – 2 = +2h 19:00 + 2h = 21:00, still 4 September

C) Bombay (Mumbai) Difference from Rome: +5:30 − 2 = +3:30h 19:00 + 3.5h = 22:30, still 4 September

D) Lima (Peru) Not on the list, but relatable to New York’s offset.

Difference from Rome: −5 − 2 = −7h 19:00 − 7h = 12:00, same day (4 September), just much earlier in the day

E) Cape Town (South Africa) Southern Africa sits at UTC+2, which — coincidentally — matches Rome's summer offset exactly Same local time as Rome: 19:00, 4 September Conclusion:

A) Seoul — only city far enough ahead (+7h relative to Rome) to have already crossed into 5 September.

Full explanation

There are 5 major lines of latitude on Earth shaped by our planet’s tilt, which are the Equator (0’), Tropic of Cancer (23° 26' N), Tropic of Capricorn (23° 26' S), Arctic Circle (66° 33' N), and Antarctic Circle (66° 33' S).

The Equator divides the Earth into the Southern and Northern hemispheres.

The Earth rotates on its axis and orbits the Sun in an elliptical path once a year.

Because Earth’s axis is tilted at 23.5°, this revolution creates our seasons.

On 20–21 June (the summer solstice in the Northern Hemisphere), the Earth's axial tilt (23.5°) points the Northern Hemisphere maximally toward the Sun, placing the Sun directly overhead (at zenith) along the Tropic of Cancer (23.5°N).

Other options Equator — The Sun is at zenith over the equator only at the equinoxes (~20 March and ~22 September), not the solstices.

South Pole — On 20 June, the South Pole is in polar night (continuous darkness) — it's the winter solstice for the Southern Hemisphere, the exact opposite condition.

Tropic of Capricorn — This is where the Sun is at zenith on the opposite solstice (~21 December), corresponding to Southern Hemisphere summer.

North Pole — At the North Pole on 20 June, the Sun is visible all day (polar day) but sits low on the horizon — it is never directly overhead there, since the Pole is at 90°N, beyond the tropics' reach.

Full explanation

Solution Fermi designed and led the construction of Chicago Pile-1 (CP-1), built under the stands of Stagg Field at the University of Chicago, which achieved the first controlled, self-sustaining nuclear chain reaction on 2 December 1942.

Niels Bohr — Danish physicist who developed key theoretical models of atomic structure and contributed to early nuclear fission theory (with John Wheeler), but did not design or build the reactor itself.

Julius Robert Oppenheimer — Scientific director of the Manhattan Project at Los Alamos, responsible for designing the atomic bomb, not the original test reactor.

His role came later and was weapons-focused, not the foundational chain-reaction experiment.

Marie Curie — Pioneered research on radioactivity (discovering polonium and radium) decades earlier; she died in 1934, before nuclear fission was even discovered (1938), so she had no involvement in reactor construction.

Albert Einstein — Provided the theoretical foundation (E=mc²) and famously co-signed the letter to President Roosevelt warning about nuclear weapons potential, but he was a theoretical physicist with no hands-on role in reactor design or construction.

Full explanation

C) Mattarella – Napolitano – Ciampi – Scalfaro This lists the last four presidents in reverse chronological order (most recent first, going backward).

The actual order of service (oldest to newest): Oscar Luigi Scalfaro: 1992–1999 Carlo Azeglio Ciampi: 1999–2006 Giorgio Napolitano: 2006–2015 Sergio Mattarella: 2015–present

Full explanation

Asimov introduced the Three Laws of Robotics in his science fiction works, most notably in the short story collection I, Robot (1950) and earlier in the 1942 story "Runaround." The laws became a foundational concept in science fiction and are still referenced in real discussions of AI ethics and robotics today.

John R. R. Tolkien — Author of The Lord of the Rings and The Hobbit; his work is high fantasy (Middle-earth, elves, hobbits), with no connection to robotics or science fiction laws.

Joanne K. Rowling — Author of the Harry Potter series; fantasy genre centered on wizards and magic, unrelated to robotics.

Clive S. Lewis — Author of The Chronicles of Narnia; also wrote Christian apologetics and some science fiction (the Space Trilogy), but he is not associated with robotics or the Three Laws.

Vladimir D. Nabokov — Russian-American novelist best known for Lolita; a literary fiction writer with no connection to science fiction or robotics themes.

Full explanation

The 2002 outbreak in China refers to SARS (Severe Acute Respiratory Syndrome), caused by the coronavirus SARS-CoV. It emerged in Guangdong province, China, in November 2002 and spread to over two dozen countries before being contained in 2003.

MERS — Middle East Respiratory Syndrome, caused by a different coronavirus (MERS-CoV), first identified in Saudi Arabia in 2012 — a separate outbreak a decade later.

HIV — Human Immunodeficiency Virus, a retrovirus causing AIDS; transmitted very differently (bloodborne/sexual contact, not respiratory) and unrelated to coronaviruses.

EBOLA — Caused by the Ebola virus (a filovirus, not a coronavirus), associated with hemorrhagic fever, first identified in 1976 in Central Africa — different virus family, different region, different era.

Spanish flu — An influenza pandemic (H1N1 virus, not a coronavirus) that occurred in 1918, nearly a century before this outbreak.

Full explanation

In Italian, celere means swift/rapid, which is synonymous with prompt (Sollecito in Italian).

It is also the name of a famous rapid-response police unit (Reparto Celere) in Italy.

Therefore, it has a semantic connection with both words.

Full explanation

This is a logical deduction question where the trap is mistaking "did not increase" for "necessarily decreased." The original statement only tells us Thalasso was different from the other pools in that it increased — it says nothing about whether the others decreased or simply stayed flat (no change).

Full explanation

This is a counting problem with a key trap: the word "modify" means we must exclude the original flag's color combination from the count.

Circle color options: Red, Green, or Blue (additive primaries) → 3 choices Background color options: White or Black → 2 choices Total combinations (without restriction): 3 × 2 = 6 But one of these 6 combinations — Red circle + White background — is the original, unmodified Japanese flag.

Since the question asks for ways to modify it, this combination must be excluded (it's not a change at all).

Final count: 6 − 1 = 5

Full explanation

Let’s solve the first part first, to have 3-digit numbers from the given equation: m = (n+1)(n + 2)(n + 3) Testing values of n: n = 2: 3 x 4 x 5 = 60 (too small – two digits) n = 3: 4 x 5 x 6 = 120 n = 4: 5 x 6 x 7 = 210 n = 5: 6 x 7 x 8 = 336 n = 6: 7 x 8 x 9 = 504 n = 7: 8 x 9 x 10 = 720 n = 8: 9 x 10 x 11 = 990 n = 9: 10 x 11 x 12 = 1320 (too big – 4 digits) So, 6 “n” numbers give 3-digit numbers.

(i.e., n=3,4,5,6,7,8) Next, checking divisibility by 7: since m = = (n+1)(n + 2)(n + 3), m is divisible by 7 whenever 7 is one of the 3 consecutive numbers.

Dividable cases: n = 4: 5 x 6 x 7 = 210 n = 5: 6 x 7 x 8 = 336 n = 6: 7 x 8 x 9 = 504 So, 3 “n” values satisfy the criteria.

Full explanation

Step-by-step deduction: Setup: Three friends, exactly two born in Rome, one born in Milan.

Clue 4 tells us the Milan-born friend is either Enea or Giorgio (not Nicolò) — so we test both cases.

If Enea is in Milan and Giorgio is in Rome, Nicolo must be Rome (to reach the total of 2 Rome).

This case is consistent with the clue: “"if Nicolò is Rome, then Giorgio is Rome".

It is also consistent with the second clue: "if Enea is Rome, then Nicolò is Rome".

So, this case works.

If Giorgio is in Milan and Enea is in Rome, Nicolo must be Rome (to reach 2 Rome total).

This is not consistent with the clue: "if Nicolò is Rome, then Giorgio is Rome".

Therefore, this case is impossible.

Therefore, the correct answer is

A) Giorgio and Nicolo were born in Rome.

Full explanation

Setting up the equation: Let m = number of meat dishes, f = number of fish dishes.

Cost equation: 11m + 13f = 107 Constraint: m + f < 10 (fewer than ten people total) We will solve this by testing the number of fish dishes mentioned in the answer options.

If we solve for m and the result is an integer, it can work as the right number.

Option

A) 9 If f = 9, 13f costs 117, which is greater than 107.

So, Option

B) 5 If f = 5, m = (107 – 13f)/11 = 3.82 (not an integer) doesn’t work Option

C) 2 If f = 2, m = (107 – 13f)/11 = 7.36 (not an integer) doesn’t work Option

D) 4 If f = 4, m = (107 – 13f)/11 = 5 (an integer – satisfy the equation) Option

E) 7 If f = 7, m = (107 – 13f)/11 = 1.45 (not an integer) doesn’t work

Therefore, the correct answer is option

D) 4.

Full explanation

Green gold is composed of a ratio of 75% gold, 12.5% copper, and 12.5% silver.

Starting with 60g of gold, we need to determine the required grams of silver and copper to process the gold.

If the available stock meets these requirements, we can calculate the total grams of green gold.

For 60g of gold, 10g of copper, and 10 g of silver are required (0.125 x 80).

The in-stock amount can well supply the required amount.

Therefore, the total grams of green gold would be 80g (60 + 10 + 10).

Full explanation

3 pieces of information are given to find the number of club members.

Alice received three times as many votes as the other candidate was elected with exactly 66% of the votes of eligible members 18 members did not vote If we set up an equation out of the given information with T as the total number of club members, Alice’s votes = 0.66 T Other candidates’ votes = Alice votes / 3 = 0.66T / 3 = 0.22T Total votes cast = 0.66T + 0.22 T = 0.88 T – equation 1 Total votes cast = T – 18 (using 3rd information) – equation 2 Setting the 2 equations equal: 0.88 T = T – 18 18 = T – 0.88 T = 0.12 T T = 18 / 0.12 = 150

Full explanation

We are told that for the A-series paper sizes: The ratio of length to width is always √2.

Each new size is obtained by halving the previous sheet along its longer side.

The dimensions of A0 are Length = LU Width = LA So, A0 is LU x LA When we cut A0 in half along its longer side, we get A1: LA x LU/2 Now, LU/2 becomes the shorter side of, and LA becomes the longer side of A1.

Tracking through each halving:

Hence, the correct answer is

B) LU/4

Full explanation

This problem can be solved using mathematical knowledge and functions.

The operation given: a ◊ b = ab – a – b We need to calculate: (a ◊ b) ◊ c – (a ◊ c) ◊ b

Step 1: Calculate (a ◊ b) ◊ c (a ◊ b) ◊ c = (ab−a−b)c−(ab−a−b)−c. = abc – ac – bc – ab + a + b – c

Step 2: Calculate a ◊ c a ◊ c = ac – a – c (a ◊ c) ◊ b = (ac – a − c) b − (ac − a−c ) – b = abc−ab−bc−ac+a+c−b.

Solving (a ◊ b) ◊ c – (a ◊ c) ◊ b = (abc−ac−bc−ab+a+b−c)−(abc−ab−bc−ac+a+c−b) = abc−ac−bc−ab+a+b−c−abc+ab+bc+ac−a−c+b. = 2b – 2c

Full explanation

Eosinophils are a type of white blood cell (leukocyte) belonging to the group of granulocytes, so named because their cytoplasm contains numerous granules visible under the microscope.

They play an important role in Defense against parasitic infections (especially helminths) Allergic reactions (e.g., asthma, hay fever) Modulation of inflammatory responses Other granulocytes are neutrophils and basophils.

Lymphocytes and monocytes are agranulocytes.

They are produced in the bone marrow (not bone tissue) through the process of hematopoiesis.

Full explanation

The nephron is the structural and functional unit of the kidney.

Each human kidney contains approximately 1 million nephrons, and each nephron is responsible for: Filtering blood Reabsorbing useful substances (water, glucose, ions) Secreting certain substances into the urine Producing urine A nephron consists of 2 parts: the renal corpuscle and the renal tubule.

A nephron is neither an exocrine gland nor an endocrine gland, excluding option A, D and E. The functional unit of the nervous system is the neuron, excluding option B.

Full explanation

The capsid is the protein shell that surrounds the genetic material of a virus.

It is composed of protein subunits called capsomeres and serves several important functions: Protects the viral nucleic acid (DNA or RNA) Helps the virus attach to and enter host cells Gives the virus its characteristic shape (icosahedral/ helical) A virus consists minimally of genetic material and a capsid.

Some viruses additionally possess an envelope surrounding the capsid.

Full explanation

The cardiac conduction system is a specialized network of cardiac muscle cells responsible for generating and transmitting electrical impulses that coordinate the heartbeat.

The main components of the conduction system are: Sinoatrial (SA) node – the natural pacemaker of the heart Atrioventricular (AV) node Bundle of His (atrioventricular bundle) Right and left bundle branches Purkinje fibers The electrical impulse normally follows this pathway: SA node → atria → AV node → Bundle of His → bundle branches → Purkinje fibers → ventricular myocardium

Full explanation

The given options are about the pancreas.

The pancreas is a mixed gland, meaning that it has both: Exocrine functions, involving the secretion of digestive enzymes into the duodenum.

Endocrine functions, involving the secretion of hormones (insulin, glucagon, etc) directly into the bloodstream.

The pancreas parenchyma carries out exocrine functions, and the endocrine functions are carried out by the islets of Langerhans.

Therefore, the only incorrect statement is option

A) since pancreatic secretions are released into the duodenum, not into the stomach.

Full explanation

The spinal cord is part of the central nervous system (CNS) and is characterized by: Grey matter, located centrally and containing mainly neuronal cell bodies, dendrites, and synapses.

White matter, located peripherally and consisting mainly of myelinated axons.

(ruling out option

C) The spinal cord is surrounded by the same three meninges that cover the brain: dura mater, arachnoid mater, and pia mater.

In the CNS, the cells responsible for producing the myelin sheath are oligodendrocytes, whereas in the peripheral nervous system (PNS), myelin is produced by Schwann cells.

(Ruling out options A and

B) A cross-section of the spinal cord shows: Dorsal (posterior) horns, primarily involved in sensory processing.

(Ruling out option

D) Ventral (anterior) horns, containing the cell bodies of somatic motor neurons.

Hence, the correct answer is Option E.

Full explanation

The famous experiment by Alfred Hershey and Martha Chase (1952) demonstrated that DNA, and not protein, is the genetic material.

They worked with bacteriophages, viruses that infect bacteria.

A bacteriophage consists essentially of: DNA A protein capsid The key idea of the experiment was to label DNA and proteins with different radioactive isotopes.

Sulphur and Phosphorus work because: DNA contains phosphorus but essentially no sulfur.

Proteins may contain sulfur but do not contain the phosphorus-rich backbone characteristic of nucleic acids.

After allowing the phages to infect bacteria, Hershey and Chase found that ^32P entered the bacterial cells, while ^35S remained outside, demonstrating that DNA was the hereditary material.

Therefore, the correct option is option A.

Full explanation

There are 2 blood group systems involved.

ABO system: Parents: Mother: O → genotype ii Father: AB → genotype IA IB possible children: IAi → blood group A IBi → blood group B We can determine the answer by eliminating the options that do not include blood group A or B.

Rh system:

Parents: Mother: Rh– → dd Father: Rh+ heterozygous → Dd

Possible children: Dd: Rh+ Dd: Rh-

Possible children: A Rh+ A Rh– B Rh+ B Rh–

Final Answer:

C) B Rh–

Full explanation

The phenomenon described involves the movement of water across a selectively permeable membrane, specifically the tonoplast (vacuolar membrane) in plant cells.

This movement of water depends on the solute concentration difference between the inside and outside of the cell: Hypotonic solution (outside has lower solute concentration): Water enters the cell → vacuole swells (turgid cell) Hypertonic solution (outside has higher solute concentration): Water leaves the cell → vacuole shrinks (plasmolysis) This passive movement of water is called osmosis.

Full explanation

We are told: the 9th nucleotide (G) is replaced by A. Let’s number nucleotides: AUG (1–3) CCA (4–6) UGG (7–9) ← mutation here So, the third codon is UGA after mutation.

We memorized that the stop codons are UAA, UGA, and UAG. So, the mutation changes Trp to a stop codon, causing premature termination of translation.

Therefore, the amino acid chain would be only Met–Pro–end.

Full explanation

The lac operon is a classic example of a regulatable (inducible) gene system in prokaryotes (e.g., E. coli).

It controls the production of enzymes needed to metabolize lactose, mainly: β-galactosidase (often referred to in exams as “lactase”) Permease (for lactose entry) Transacetylase (accessory role) The key idea is: The lac operon is OFF by default and turns ON only when lactose is available.

No lactose present → repressor binds → operon OFF Lactose present → allolactose inactivates repressor → operon ON So, the cell only produces lactose-digesting enzymes when lactose is actually available to be used.

Also, expression is not proportional to “excess” lactose; it is triggered by the presence, not the quantity, beyond a threshold.

Therefore, the correct option is option

C) When lactose is present in the medium.

Full explanation

BamHI recognizes the palindromic sequence GGATCC (read 5'→3' on both strands) and cuts between the two G's on each strand, not straight across: 5'-G / GATCC-3' and 3'-CCTAG / G-5'.

Because the two cuts are offset rather than directly opposite each other, each resulting fragment ends in a short single-stranded overhang (GATC) — this staggered cut is what makes the ends 'sticky' rather than blunt.

The given sequence (5'...ATGGATCCGGACTAA...3') contains only one BamHI recognition site, so a single cut produces exactly 2 fragments, each with a sticky end — matching option A.

Full explanation

Adult human heart muscle cells (cardiomyocytes) are considered terminally differentiated cells.

After completing development, they permanently exit the active cell cycle and enter a quiescent state called the G0 phase.

Examples of cells in G0 include: Adult cardiomyocytes Most neurons Skeletal muscle fibers

Full explanation

Meiosis consists of two successive divisions: Meiosis I (reductional division) Meiosis II (equational division) The defining event of Meiosis I is the separation of homologous chromosomes, reducing the chromosome number from diploid (2n) to haploid (n).

During Meiosis II, sister chromatids separate.

(This excludes the option

B) At the end of Meiosis I, there are only 2 haploid cells.

The four haploid cells are produced only after completion of Meiosis II. (This excludes the option

C) DNA replication occurs before meiosis begins, during the S phase of interphase.

Also, there is no DNA replication between Meiosis I and Meiosis II. (This excludes the option

D) During prophase I, homologous chromosomes may undergo crossing over, exchanging segments of DNA. As a result, sister chromatids may no longer be genetically identical.

(This excludes option E).

Hence, the correct answer is option

A) Homologous chromosomes separate

Full explanation

Analysis of each option Option

A) Cytoskeleton – Intracellular digestion This statement is incorrect.

The cytoskeleton is a network of protein filaments composed of microfilaments, intermediate filaments, and microtubules.

Its functions include maintaining cell shape, intracellular transport, cell movement, and cell division.

It does not carry out intracellular digestion.

Intracellular digestion is carried out primarily by lysosomes.

Option

B) Smooth ER – Protein synthesis This statement is incorrect.

The smooth ER is involved in lipid synthesis, detoxification, and calcium storage, not in protein synthesis.

Protein synthesis occurs on free ribosomes and bound ribosomes attached to the rough ER. Option

C) Nucleolus – synthesis of rRNA This statement is correct.

The nucleolus is the site of transcription of ribosomal RNA genes, processing of rRNA, and assembly of ribosomal subunits.

These subunits are then exported to the cytoplasm to participate in protein synthesis.

Option

D) Golgi apparatus – Cell movement This statement is incorrect.

The Golgi apparatus functions in the modification of proteins, sorting and packaging of proteins, and the formation of secretory vesicles (such as lysosomes).

Option

E) Lysosomes – Cellular respiration This statement is incorrect.

Lysosomes contain hydrolytic enzymes responsible for: Intracellular digestion, Degradation of macromolecules, Recycling of cellular components.

Cellular respiration and ATP production occur in the mitochondria.

Full explanation

The endomembrane system is a group of membrane-bound organelles in eukaryotic cells that are functionally connected through the synthesis, modification, transport, and degradation of proteins and lipids.

The major components of the endomembrane system include: Nuclear envelope Rough endoplasmic reticulum (RER) Smooth endoplasmic reticulum (SER) Golgi apparatus Lysosomes Transport and secretory vesicles Plasma membrane These structures communicate through membrane budding and fusion.

Mitochondria are not part of the endomembrane system because they are independent organelles with their own DNA, their own ribosomes, a double membrane, and no participation in vesicular trafficking.

Therefore, the correct answer is option

A) Mitochondria.

Full explanation

Photosynthesis occurs in two major stages: Light-dependent reactions (light phase) – occur in the thylakoid membranes of chloroplasts.

Calvin cycle (light-independent reactions or dark phase) – occur in the stroma of chloroplasts.

The purpose of the light phase is to convert light energy into chemical energy, producing molecules that power the Calvin cycle.

The two essential products are: ATP: provides the energy required for carbon fixation and sugar synthesis.

NADPH: provides the reducing power (electrons and hydrogen) needed to reduce carbon compounds into carbohydrates.

The Calvin cycle then uses CO₂, ATP, and NADPH to synthesize sugars.

Hence, the correct answer is option

C) ATP and NADPH.

Full explanation

Root cells of terrestrial plants are generally non-photosynthetic and therefore do not contain chloroplasts.

Chloroplasts are organelles specialized for photosynthesis and are found mainly in the green parts of plants, such as leaves and young stems, where light is available.

Full explanation

Each MnO•Mn₂O₃ contains 3 manganese atoms, so: d = 3a Each MnO•Mn₂O₃ contains 4 oxygen atoms, while each Al₂O₃ contains 3 oxygen atoms.

The smallest whole numbers satisfying this relation are a = 3 and c = 4, with 12 oxygen atoms on each side of the equation. 4 molecules of Al₂O₃ contains 8 aluminium atoms, so b = 8.

Since a = 3, d = 3a = 9.

Thus, balanced equation is 3 MnO•Mn₂O₃ + 8 Al → 4 Al₂O₃ + 9 Mn

Full explanation

Strontium hydroxide, Sr(OH)₂, is a strong base that dissociates completely.

To find the molar concentration, we need to calculate the hydrogen ion concentration first and relate the concentration to the concentration of Sr(OH)₂.

Given: pH = 12 pOH = 14 – 12 = 2 [OH^-]=10^(-pH) [OH^-]=10^-2 M=0.01 M Strontium hydroxide is a strong base and dissociates completely: Sr(OH)₂→Sr⁽²⁺⁾+2 OH^- Notice that one mole of Sr(OH)2 produces 2 moles of OH- Therefore, molar concentration of Sr(OH)₂ = 0.01M/2=0.005 M=5×10^-3M

Full explanation

Analysis of each option Option

A) H₂Se, F₂ H₂Se is a polar molecule, and F₂ is a nonpolar molecule.

The interaction between polar and nonpolar molecules would be dipole-induced dipole, not dipole-dipole.

Option

B) O₂, H₂ Both are nonpolar molecules, with only London dispersion forces between them.

Option

C) H₂, H₂O H₂ is nonpolar while H₂O is polar.

Polar + nonpolar results in dipole-induced dipole, not dipole-dipole interaction.

Option

D) HCl, CHCl₃ Both HCl and CHCl₃ are polar molecules, establishing permanent dipole – permanent dipole interactions.

Option

E) F₂, Cl₂ Both are nonpolar molecules.

So, only dispersion forces exist between them.

Full explanation

Given: Initial state: n₁=1.0 mol V₁=V Final state: Moles added: 3.0 mol → n₂=4.0 mol Volume doubles → V₂=2V Question: how will the pressure change compared to the original pressure inside the same balloon?

We can use ideal gas law equation to solve this.

PV = nRT Since T is constant and R is constant, if we compare the initial and final states: P₂/P₁= (n₂/V₂)/(n₁/V₁)= n₂V₁/n₁V₂=4.0⋅V/1.0⋅2V =2 So, P₂=2 P₁

Full explanation

Analysis of the given options Option A: Amides contain the carbonyl group Amides have the general structure: R-CO-NH₂.

So, they contain a carbonyl group (C=O) as one of the functional groups.

Hence, this is a correct statement.

Option B: Amides contain no nitrogen This is false.

Amides are defined by the presence of an amino group which contains nitrogen.

Option C: Aldehydes lack a carbonyl group This is false.

Aldehydes do contain a carbonyl group at the end of the chain: R-CHO. Option D: Alcohols always have double covalent bonds This is false.

Alcohols contain only single bonds.

No double bonds are required.

(R-OH) Option E: Alkenes always have triple carbon–carbon bonds This is false.

Alkenes contain one or more C=C double bonds.

Tripe bonds are found in alkynes, not alkenes.

Full explanation

Lithium (Li) has atomic number of 3, so a neutral Li atom has: Li:1s² 2s¹ A Li⁺ ion means: It has lost one electron Electrons are removed from the highest energy level first, so: When the 2s electron is removed: 1s² 2s¹→1s² Final configuration of Li⁺ = 1s²

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Analysis of the given options

A) NF₃ - Nitrogen is the central atom. - Nitrogen has 5 valence electrons. - It forms 3 single bonds with F atoms → 6 bonding electrons. - It also has 1 lone pair (2 electrons).

So nitrogen has: 6 (bonding)+2 (lone pair)=8 electrons (Octet satisfied)

B) BF₃ - Boron has 3 valence electrons. - It forms 3 bonds with fluorine, so 6 electrons around B. (electron-deficient)

C) PF₅ - Phosphorus forms 5 bonds, so 10 electrons around P. (expanded octet)

D) NO - NO is a radical having an odd number of electrons.

Therefore, the octet rule is not satisfied.

E) BrO₂ - Bromine is a period 4 element and typically expands its octet.

So, in BrO₂, bromine does not obey the octet rule.

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A molecule has an octahedral geometry when the central atom has: 6 bonding pairs 0 lone pairs Among the given options, only SeF₆ satisfy the criteria.

PF₅ has a trigonal bipyramidal geometry.

BrF₃ has a T shape, and SF₄ has a seesaw shape.

BF₃ has a trigonal planar geometry.

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Write balanced equation first: 2 H₂ + O₂ → 2H₂O Then, find the limiting reagent: The chamber contains 10 moles of H₂ and 7 moles of O₂.

From the equation, 2 moles of H₂ needs 1 moles of O₂ Therefore, 10 moles of H₂ needs 5 moles of O₂.

We have 7 moles of O₂, so H₂ is the limiting reagent.

If all 10 mol of H₂ are reacted completely, 10 mol of H₂O will be produced.

Remaining mass after reaction = mass of product + mass of unused reactant = 10 mol of H₂O + 2 moles of O₂ = 12 moles

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We use the molarity formula: M = n/V Find the moles of NaOH: n=10g/(40g/mol )=0.25 mol Then, solve for V: V=n/M=0.25/5=0.05 l=50 ml

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First, write the dissolution equilibrium: Zn(OH)₂(s)⇌Zn⁽²⁺⁾+2OH^- The solubility product is: K_(sp)=[Zn⁽²⁺⁾][OH^-]² K_(sp) depends only on temperature It does not depend on pH or ion concentrations However, solubility does change when you add common ions (like OH^- or Zn²⁺) Analysis of each option

A) Does not depend on temperature  Wrong.

K_(sp) does depend on temperature.

B) Does not depend on pH  Correct.

K_(sp) is independent of pH. (pH can affect solubility, but not the value of K_(sp) itself.)

C) Solubility does not change if NaOH is added  Wrong.

NaOH increases OH^- → common ion effect → solubility decreases.

D) K_(sp) changes if ZnCl₂ is added  Wrong.

Adding ions does not change K_(sp), only temperature does.

E) Solubility does not change if ZnCl₂ is added  Wrong.

Zn²⁺ is a common ion → solubility decreases.

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The given solution is a buffer solution.

Weak acid: formic acid (HCOOH) = 0.4 M Conjugate base: formate (HCOO^- from sodium formate) = 1.0 M So we use Henderson–Hasselbalch: pH=pK_a+log(([A^-])/[HA]) If the whole solution is diluted 10-fold: [HCOOH] → 0.4/10 = 0.04 M, and [HCOO^-] → 1.0/10 = 0.1 M. Now check the ratio: ([A^-])/[HA]=0.1/0.04=2.5 Original ratio: 1.0/0.4=2.5 The ratio stays the same.

Therefore, the pH remains unchanged (4.15).

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Let’s solve this step by step.

Given: AM = 5 cm (median from vertex A to midpoint M of BC) tan(∠ACB) = 5/13

Step 1: Geometry of the isosceles triangle Since AB = AC, the median from vertex A to base BC is also the altitude.

Therefore AM ⟂ BC and M is the midpoint of BC.

Step 2: Apply trigonometry in right triangle AMC =>tan(∠ACM)=AM/MC =>5/13=5/(BC/2) =>BC/2=13 =>BC=26 cm

So, the correct answer is option D.

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Let’s solve this step by step.

Step 1: Factorise the left-hand side =>4x²-y²=(2x+y)(2x-y)=0

Step 2: Identify the two straight lines =>y=2x =>y=-2x Each equation defines a straight line through the origin.

Together they form a pair of intersecting straight lines.

So, the correct answer is option C.

Full explanation

Let’s solve this step by step.

Step 1: Rewrite 4^x in base 2 =>4^x=2^(2x) The equation becomes: =>2^(2x)+2^(3x+16)=0

Step 2: Analyse the sign of each term For all x∈R: =>2^(2x)>0 =>2^(3x+16)>0 The sum of two strictly positive quantities is always strictly positive and can never equal zero.

The equation has no real solutions.

So, the correct answer is option E.

Full explanation

Let’s solve this step by step.

Step 1: Square both sides (both sides ≥ 0, so the inequality direction is preserved) =>(x-1)²<x²

Step 2: Expand the left side =>x²-2x+1<x²

Step 3: Simplify and solve for x =>-2x+1<0 =>2x>1 =>x>1/2

So, the correct answer is option A.

Full explanation

Let’s solve this step by step.

Given: x=3t² mandy=4t² m

Step 1: Show the trajectory is a straight line =>y/x=4t²/3t²=4/3=const Since y/x is constant, the path is the straight line y=4/3x.

Step 2: Compute the velocity components =>v_x=dx/dt=6t m/s =>v_y=dy/dt=8t m/s Speed increases linearly with t — the motion is uniformly accelerated.

Step 3: Compute the acceleration components =>a_x=d²x/dt²=6 m/s² =>a_y=d²y/dt²=8 m/s²

Step 4: Compute the magnitude of acceleration =>∣a∣=√(a_x²+a_y²)=√(36+64)=√(100)=10 m/s²

So, the correct answer is option E.

Full explanation

Let's solve this step by step.

Given: k=8 N/m T=1 s

Step 1: Write the period formula for a mass–spring system T=2π√(m/k)

Step 2: Square both sides and isolate m: T²=4π²m/k m=kT²/4π²

Step 3: Substitute values m=8×1²/4π² m=2/π²~2/10~0.2 kg

So, the correct answer is option B.

Full explanation

Let's solve this step by step.

Given: P₁=5 atm V₁=3 m³ P₂=15 atm

Step 1: Apply Boyle’s Law (isothermal process: T=constant) P₁V₁=P₂V₂

Step 2: Solve for V₂: V₂=P₁V₁/P₂ V₂=5×3/15 V₂=15/15=1 m³

So, the correct answer is option C.

Full explanation

Let's solve this step by step.

Given: C₁=8 μF, C₂=12 μF (in series with each other) C₃=20 μF, C₄=5 μF (in parallel with the series pair)

Step 1: Equivalent capacitance of C₁ and C₂ in series C₍₁₂₎=C₁C₂/(C₁+C₂) C₍₁₂₎=8×12/(8+12) C₍₁₂₎=96/20=4.8 μF

Step 2: Add the three parallel branches C_(eq)=C₍₁₂₎+C₃+C₄ C_(eq)=4.8+20+5=29.8 μF

So, the correct answer is option A.