DCOA Mixed Practice Test #363

Question 1

Nylon 6,6 is a synthetic polymer renowned for its high tensile strength, elasticity, and abrasion resistance, making it suitable for various industrial applications. Considering its chemical structure and synthesis, which of the following statements accurately describes the formation and a key application of Nylon 6,6?

Accepted Answer

B. It is formed by the condensation polymerization of hexamethylenediamine and adipic acid, and is primarily used in manufacturing ropes and fabrics. — Nylon 6,6 is a polyamide synthesized through condensation polymerization, involving the reaction between hexamethylenediamine and adipic acid, where water molecules are eliminated. Its robust mechanical properties, including high tensile strength and abrasion resistance, make it ideal for industrial applications such as ropes, textiles, and engineering plastics. Option A describes Nylon 6 and misidentifies its application; Option C describes polyethylene/polypropylene and misidentifies the application; Option D describes Polyethylene Terephthalate (PET).

Answer

A. It is formed by the addition polymerization of caprolactam and is primarily used in manufacturing electrical insulators.

Answer

C. It is formed by the addition polymerization of ethene and propene monomers, and is primarily used in non-stick coatings.

Answer

D. It is formed by the condensation polymerization of terephthalic acid and ethylene glycol, and is primarily used in making high-strength plastic bottles.

Question 2

Pambar of Kerala:‌​‍

Accepted Answer

Cauvery tributary — Tributary of Cauvery (Idukki).‌​‍

Answer

None

Answer

Joins Pamba

Answer

Western

Question 3

Deficiency of Vitamin B1 (Thiamine) can significantly impair the activity of which crucial enzyme complex involved in the oxidative decarboxylation of pyruvate?

Accepted Answer

B. Pyruvate dehydrogenase complex — Thiamine pyrophosphate (TPP), derived from Vitamin B1, is an essential coenzyme for the pyruvate dehydrogenase complex (PDC). PDC catalyzes the conversion of pyruvate to acetyl-CoA, a critical link between glycolysis and the citric acid cycle. Impaired PDC activity leads to reduced ATP production and lactate accumulation, characteristic of thiamine deficiency.

Answer

A. Lactate dehydrogenase

Answer

C. Succinate dehydrogenase

Answer

D. Glucose-6-phosphate dehydrogenase

Question 4

WTO (World Trade Organization) replaced:‌​‍

Accepted Answer

GATT (General Agreement on Tariffs and Trade) — 1995 — WTO established 1 January 1995 after Uruguay Round (GATT 1947). ‌​‍Based in Geneva. Enforces multilateral trade rules. ‌​‍164 members.

Answer

UN

Answer

IMF

Answer

EU

Question 5

Trypsin is secreted by:‌​‍

Accepted Answer

Pancreas (as trypsinogen, activated by enterokinase) — Protease. ‌​‍Cleaves peptides on C-terminal of K and R. Bile (from liver) emulsifies fats — not an enzyme.

Answer

Salivary glands

Answer

Liver

Answer

Stomach

Question 6

Mars called:‌​‍

Accepted Answer

Red Planet — Red Planet (iron oxide surface).‌​‍

Answer

Morning Star

Answer

Blue Planet

Answer

Evening Star

Question 7

A teacher observes that a few students are consistently disengaged during group work, often sitting quietly and not contributing to discussions. To encourage their participation and engagement, which strategy would be most effective?

Accepted Answer

B. Providing specific, positive feedback when they make even small contributions or attempts to participate. — Specific positive feedback reinforces desired behaviors and builds confidence, making students more likely to participate in the future. Forcing leadership roles or threatening grade reductions can increase anxiety and disengagement, while ignoring the issue does not address the problem proactively.

Answer

A. Assigning them leadership roles in every group to force participation.

Answer

C. Threatening to lower their group project grades if they do not speak up more.

Answer

D. Ignoring their lack of participation, assuming they will contribute when ready.

Question 8

International Court of Justice (ICJ) is:‌​‍

Accepted Answer

Principal judicial organ of UN, in The Hague — ICJ (World Court) founded 1945. ‌​‍15 judges elected by UNGA + UNSC for 9 years. India's Dalveer Bhandari currently (2024) on ICJ.

Answer

Private court

Answer

Private dispute resolution

Answer

US court

Question 9

The International Court of Justice (ICJ) has the authority to adjudicate disputes between states. Which of the following is a key limitation of the ICJ's jurisdiction?

Accepted Answer

C. States must consent to the ICJ's jurisdiction, either through treaties or optional clause declarations. — The ICJ's jurisdiction is based on the consent of states, which can be given through treaties, optional clause declarations under Article 36 of the ICJ Statute, or ad hoc agreements. The court cannot unilaterally impose its jurisdiction (option C is correct as the limitation).

Answer

A. The ICJ can only hear cases referred to it by the UN Security Council.

Answer

B. The ICJ's jurisdiction is limited to disputes involving only member states of the United Nations.

Answer

D. The ICJ can enforce its rulings without requiring the consent of the involved states.

Question 10

A 16-year-old student consistently struggles with impulse control, often making risky decisions without considering long-term consequences. This behavior is most likely linked to the underdevelopment of which brain region?

Accepted Answer

A. Prefrontal cortex — The prefrontal cortex, responsible for impulse control, decision-making, and executive functions, matures later in adolescence (into the mid-20s). The amygdala (B) regulates emotions but is fully developed by adolescence. The hippocampus (C) is involved in memory, and the cerebellum (D) in motor coordination—they are not primarily linked to impulse control.

Answer

B. Amygdala

Answer

C. Hippocampus

Answer

D. Cerebellum

DCOA Mixed Practice Test #363