Mushkovic



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Qualification Intermediate/A-level
Subject BIOLOGY
Country United States
Gender Male
Mushkovic CHEMISTRY   -   Chemistry

The products of the fermentation of a sugar are ethanol and:

During fermentation, sugars such as glucose are converted by yeast or bacteria into ethanol and carbon dioxide. The general equation for this process is: C 6 H 12 O 6 → 2 C 2 H 5 OH + 2 CO 2 C 6 ​ H 12 ​ O 6 ​ →2C 2 ​ H 5 ​ OH+2CO 2 ​ Thus, the products of sugar fermentation are ethanol (C2H5OH) and carbon dioxide (CO2).
Mushkovic CHEMISTRY   -   Chemistry

Aldehydes can be synthesized by the oxidation of:

Aldehydes are synthesized by the oxidation of primary alcohols. The oxidation process involves removing hydrogen atoms from the primary alcohol, forming an aldehyde. For example, the oxidation of ethanol (a primary alcohol) produces acetaldehyde: CH 3 CH 2 OH → CH 3 CHO + H 2 O CH 3 ​ CH 2 ​ OH→CH 3 ​ CHO+H 2 ​ O
Mushkovic PHYSICS   -   Physics

In LED when an electron combines with a __________ during forward bias conduction, a photon of visible light is emitted.

In an LED, when an electron recombines with a hole in the p-n junction, energy is released in the form of a photon, emitting visible light.
Mushkovic PHYSICS   -   Physics

The algebraic sum of potential changes in a closed circuit is zero is Kirchhoff’s __________ rule.

Kirchhoff's second rule, also known as the voltage law (KVL), states that the sum of the electrical potential differences (voltages) around any closed circuit is zero.
Mushkovic PHYSICS   -   Physics

Which of the following lights travels the fastest in optical fibres?

Infra-red light travels fastest in optical fibers due to lower attenuation and dispersion compared to visible light.
Mushkovic PHYSICS   -   Physics

A standing wave pattern is formed when the length of string is an integral multiple of __________ wavelength.

A standing wave on a string fixed at both ends forms when the length of the string is an integral multiple of half wavelengths.
Mushkovic PHYSICS   -   Physics

Tuning of the radio is the best example of electrical __________

Tuning a radio involves adjusting the frequency of the LC circuit to resonate at the frequency of the desired radio station.
Mushkovic PHYSICS   -   Physics

A disc at rest without slipping, rolls down a hill of height (3 x 9.8) m. What is its speed in m/sec when it reaches at the bottom?

x he potential energy at the top converts to kinetic energy at the bottom. Using energy conservation: mgh = 1/2mv2. v = /2gh and h = 3 x 9.8 = 29.4 m and then v = /2 x 9.8 x 29.4 ~~ 11.4 m / s
Mushkovic PHYSICS   -   Physics

The force required to bend the normally straight path of a particle into a circular path is called __________ force.

The force that keeps a particle moving in a circular path and is directed towards the center of the circle is called centripetal force.
Mushkovic PHYSICS   -   Physics

The vertical velocity of ball thrown upward __________ with time.

When a ball is thrown upward, its vertical velocity decreases linearly with time due to the constant acceleration of gravity acting downward.
Mushkovic PHYSICS   -   Physics

__________ are the particles that experience strong nuclear force.

Particles that experience the strong nuclear force are nucleons, i.e., protons and neutrons. This force binds the nucleus together.
Mushkovic PHYSICS   -   Physics

For atomic hydrogen spectrum, which of the following series lies in visible region of electromagnetic spectrum?

The Balmer series of the hydrogen spectrum lies in the visible region. It involves transitions where the final energy level is n=2, and the initial levels are n>2.
Mushkovic PHYSICS   -   Physics

In which of the following, output is similar to NAND gate if input A=0 and input B=1.

For inputs A=0 and B=1: NAND gate outputs 1 (since 0 AND 1 is 0, and NOT 0 is 1). XOR gate outputs 1 (since XOR is true when inputs differ) Hence, the correct option is C) XOR.
Mushkovic PHYSICS   -   Physics

The Lenz’s law refers to induced __________

Lenz's Law states that the direction of the induced electromotive force (emf) will always be such that it opposes the change in magnetic flux that produced it. This is a fundamental principle in electromagnetism and is key to understanding how induction works.
Mushkovic PHYSICS   -   Physics

Resistance in RC circuit of time constant 2 seconds is 1000 Ohms. What is the value of C in the circuit?

The time constant (𝜏) for an RC circuit is given by the product of resistance (R) and capacitance (C): 𝜏 = R⋅C. given 𝜏 = 2 seconds and R = 1000 ohms: C = 𝜏 / R = 2s / 1000 ohms = 0.002 farads = 2000 μfarads however, as 2 μF aligns closely with the other options, we'll check: C = 2s / 1000 ohms = 2 x 10−3 F = 2000 μF
Mushkovic PHYSICS   -   Physics

Which one is the most stable element on the basis of binding energy?

The most stable element on the basis of binding energy per nucleon is iron (Fe). The binding energy per nucleon reaches a maximum for iron-56, which means it is the most stable nucleus. This concept is crucial in nuclear physics, as it explains why nuclear fusion occurs in stars up to iron and why heavier elements are formed by supernovae explosions.
Mushkovic PHYSICS   -   Physics

The center of Newton rings is dark due to

Newton's rings are a pattern of interference fringes. The center of Newton's rings appears dark because of destructive interference between the light waves reflected from the top and bottom surfaces of the thin air film between the lens and the glass plate.
Mushkovic PHYSICS   -   Physics

If the mass of the bob of a pendulum is doubled its time period is:

The time period of a simple pendulum is given by 𝑇 = 2𝜋 √ 𝐿 / g, where 𝐿 is the length of the pendulum and 𝑔 is the acceleration due to gravity. The mass of the bob does not affect the time period of the pendulum.
Mushkovic PHYSICS   -   Physics

What is emitted by a hot metal filament in a cathode ray tube?

A hot metal filament in a cathode ray tube emits electrons. These emitted electrons form the cathode rays that travel from the cathode to the anode within the tube.
Mushkovic PHYSICS   -   Physics

An electric charge in uniform motion produces:

An electric charge in uniform motion produces both electric and magnetic fields. The moving charge creates an electric field due to its charge and a magnetic field due to its motion.
Mushkovic PHYSICS   -   Physics

Beta ray emitted by a radioactive substance is:

Beta particles (β-) are high-energy, high-speed electrons emitted by the nucleus during radioactive decay, specifically from the transformation of a neutron into a proton within the nucleus, releasing an electron (beta particle) and an antineutrino.
Mushkovic PHYSICS   -   Physics

When a helium atom loses an electron, it becomes:

When a helium atom loses an electron, it becomes a positively charged ion (He⁺), also known as a positive helium ion. It is not an alpha particle (which consists of 2 protons and 2 neutrons), nor a proton (which is a hydrogen nucleus), nor a negative ion (which would require gaining an electron).
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

Which of the following statements about the photoelectric effect is correct?

According to the photoelectric effect, electrons are emitted from a material only if the incident light has a frequency above a certain threshold, regardless of the light's intensity.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

In the context of enzyme kinetics, what does a low Km value indicate about an enzyme's affinity for its substrate?

A low Km value indicates high affinity of an enzyme for its substrate, meaning the enzyme can achieve its maximum catalytic efficiency at low substrate concentrations.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

What type of intermolecular force is primarily responsible for the high boiling point of water?

Hydrogen bonding, which occurs between the hydrogen atom of one water molecule and the oxygen atom of another, is the primary force responsible for water's high boiling point.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

In an electrolytic cell, which of the following occurs at the cathode?

In an electrolytic cell, reduction occurs at the cathode, where electrons are gained by the species being reduced.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

Which of the following is true regarding the relationship between Gibbs free energy (ΔG) and the spontaneity of a chemical reaction?

When ΔG = 0, the system is at equilibrium, and there is no net change in the concentration of reactants and products.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

What is the main role of the enzyme carbonic anhydrase in red blood cells?

Carbonic anhydrase catalyzes the reversible conversion of carbon dioxide and water to bicarbonate and protons, which is crucial for CO2 transport in the blood.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

During oxidative phosphorylation, the energy for ATP synthesis is directly provided by:

The energy for ATP synthesis during oxidative phosphorylation comes from the proton gradient established across the inner mitochondrial membrane, which drives ATP synthase.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

Which principle explains the increase in pressure observed in a closed system when temperature is increased, assuming volume remains constant?

Gay-Lussac's Law states that the pressure of a given mass of gas varies directly with the absolute temperature when the volume is constant.
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

Which of the following describes the type of bonding and interaction within a DNA double helix?

The DNA double helix is stabilized by hydrogen bonds between complementary nitrogenous bases (adenine with thymine, and cytosine with guanine).
Mushkovic BIOLOGY   -   Chemical and Physical Foundations of Biological Systems

What is the primary function of myoglobin in muscle cells?

Myoglobin is an oxygen-binding protein in muscle cells that stores oxygen and releases it during periods of high metabolic demand, ensuring a continuous supply of oxygen for aerobic respiration.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

In a hypothetical organism, a mutation in the gene encoding for histone H1 results in defective chromatin structure. Which cellular process would most likely be affected?

Histone H1 is involved in the packaging of DNA into chromatin. Defective chromatin structure would most directly affect DNA replication, as tightly packed chromatin must be loosened to allow replication machinery access to the DNA.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

Which metabolic pathway directly produces NADPH and ribose-5-phosphate?

The pentose phosphate pathway generates NADPH for anabolic reactions and ribose-5-phosphate for nucleotide synthesis, without directly producing ATP.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

What is the primary function of the sodium-potassium pump in animal cells?

The sodium-potassium pump actively transports sodium ions out of the cell and potassium ions into the cell, which is crucial for maintaining the resting membrane potential and cell volume.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

Which of the following is a correct statement about the function of ribosomes?

Ribosomes are the cellular structures where translation occurs, converting the genetic information in mRNA into a sequence of amino acids to form proteins.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

What is the role of the enzyme DNA ligase in DNA replication?

DNA ligase is responsible for joining Okazaki fragments on the lagging strand by sealing the nicks in the sugar-phosphate backbone, ensuring the DNA is continuous.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

Which organelle is primarily responsible for the production of ATP through oxidative phosphorylation?

The mitochondrion is known as the powerhouse of the cell, where ATP is produced through oxidative phosphorylation during cellular respiration.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

In the central dogma of molecular biology, which process involves the synthesis of RNA from a DNA template?

Transcription is the process where an RNA molecule is synthesized from a DNA template, following the base pairing rules.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

Which of the following statements about the fluid mosaic model of cell membranes is correct?

The fluid mosaic model describes the cell membrane as a flexible structure where lipids and proteins can move laterally within the layer, contributing to the membrane's fluidity.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

During glycolysis, which molecule is directly converted into pyruvate?

Glycolysis converts glucose into two molecules of pyruvate through a series of steps. Glyceraldehyde-3-phosphate is an intermediate that is directly converted into pyruvate in the later stages of glycolysis.
Mushkovic BIOLOGY   -   Biological and Biochemical Foundations of Living Systems

Which of the following best describes the role of an enzyme in a biochemical reaction?

Enzymes act as catalysts that speed up biochemical reactions by lowering the activation energy required for the reaction to proceed, without being consumed in the process.