Full Exam & Question Bank: Lesson 2: The Human Immune System

Which immunoglobulin exists as a pentamer with 10 antigen-binding sites, making it highly effective in agglutination?

If a double-stranded DNA sample contains 28% Adenine, what is the exact percentage of Cytosine in this sample?

Which enzyme is responsible for linking Okazaki fragments into a continuous strand during lagging strand replication?

What is the structural characteristic of a restriction endonuclease recognition site?

Why is the genetic code described as 'degenerate' or 'redundant'?

Which of the following first-row transition metal ions exhibits the highest theoretical magnetic moment in its ground state?

The main chemical reducing agent inside the Midrex furnace and its industrial source are respectively:

A transition element whose +5 oxidation state compound (V2O5) is widely utilized as an industrial catalyst in the Contact Process for sulfuric acid manufacturing and as a colorant in ceramics is:

When dry chlorine gas is passed over red-hot iron filings, iron(III) chloride (FeCl3) is exclusively formed rather than iron(II) chloride because:

Which of the following alloys is classified as an interstitial alloy?

The electronic configurations of both Chromium (24Cr) and Copper (29Cu) are anomalous due to the enhanced stability associated with:

Concentrated nitric acid (HNO3) induces chemical passivity on the surface of iron metal due to:

The atomic radii of the elements from Chromium to Copper remain remarkably steady and nearly constant across the first transition series because of:

Magnetic iron oxide (Magnetite, Fe3O4) is chemically considered a mixed oxide because reacting it with hot concentrated sulfuric acid yields:

An aqueous solution of titanium(IV) chloride (TiCl4) is diamagnetic and colorless because:

When dilute hydrochloric acid is added to a solid salt, a gas is evolved with a pungent odor that turns acidified potassium dichromate paper green while a colloidal yellow precipitate of sulfur separates in the reaction vessel. The anion is:

To distinguish between a white precipitate of barium sulfate (BaSO4) and a white precipitate of barium phosphate (Ba3(PO4)2), one should add:

A metal cation that forms a gelatinous white precipitate with NaOH which completely redissolves in excess reagent to form a soluble clear solution is:

In a titration experiment, 20.0 mL of 0.15 M H2SO4 is completely neutralized by 30.0 mL of NaOH solution. The molar concentration of the NaOH solution is:

The indicator that exhibits a yellow color in acidic medium, blue in alkaline medium, and green in neutral medium is:

A person who skillfully makes beautiful objects by hand is called a/an ________.

While the students ________ in the art workshop, the tour guide arrived.

We visited the pottery village in Fustat ________ our holiday in Cairo.

Potters use high-temperature ovens called ________ to bake and harden clay vessels.

Electric buses and monorails produce zero exhaust fumes, making them ________ forms of transport.

Watch out! The ladder is shaking violently. You ________ fall!

I have already booked the flight tickets. I ________ to London next Friday.

The Cairo Monorail travels on an elevated single-beam track to avoid urban traffic ________.

The n-th term of an arithmetic sequence with first term a and common difference d is given by:

In the arithmetic sequence (3, 7, 11, 15, ...), the common difference d and the 20th term (T_20) are respectively:

The sum of the first n terms of an arithmetic sequence (S_n) is formulated as:

The common ratio r of the geometric sequence (64, 32, 16, 8, ...) is:

The sum to infinity (S_infinity) of a geometric series exists and converges if and only if the common ratio satisfies:

The sum to infinity of the geometric series 12 + 6 + 3 + 1.5 + ... equals:

If a, b, c form an arithmetic sequence, then the arithmetic mean b equals:

If a, b, c form a geometric sequence of positive real numbers, the geometric mean b equals:

The sum of the first 10 terms of the geometric sequence 2, 6, 18, 54, ... equals:

The number of terms in the finite arithmetic sequence (5, 9, 13, ..., 81) is:

The 7th term of the geometric sequence (2, 6, 18, ...) is:

If (x - 1, x + 2, 3x) form a geometric sequence, the positive value of x is:

The sum to infinity of the geometric series 16 + 8 + 4 + 2 + ... equals:

The derivative of f(x) = 4 x^3 - 5 x^2 + 7 x - 9 with respect to x is:

The slope of the tangent line to the curve y = x^2 - 6 x + 5 at the point (4, -3) equals:

If y = (2x + 1) * (3x - 4), then dy/dx evaluated at x = 1 equals:

Using the Quotient Rule, the derivative of y = (x + 3) / (x - 2) for x != 2 is:

According to the Chain Rule, if y = (3 x^2 - 5)^4, then dy/dx is:

The derivative of y = sin(3x) with respect to x is:

If a particle moves along a straight line such that its position s(t) = t^3 - 6 t^2 + 9 t meters, the particle comes to an instantaneous rest (velocity v(t) = 0) at times:

The equation of the tangent line to the curve y = x^3 at the point (1, 1) is:

The second derivative d^2y/dx^2 of the function y = x^4 - 2 x^3 + 5 is:

If f(x) = |x - 3|, the derivative f'(3) at x = 3:

If y = sin(3x) + cos(2x), then dy/dx at x = 0 equals:

The slope of the tangent to the curve y = (x + 1)/(x - 1) at x = 2 is:

If the tangent to y = x^2 - 4x + 5 is parallel to the x-axis, the point of tangency is:

The hydrostatic pressure exerted by a static homogeneous liquid of density rho at depth h beneath its free surface is expressed by:

A diver descends to a depth of 30 meters in seawater (density = 1030 kg/m^3). If atmospheric pressure is 1.013 x 10^5 Pa and g = 9.8 m/s^2, the total absolute pressure experienced by the diver is approximately:

Pascal's principle states that when pressure is applied to an enclosed, incompressible fluid, it is transmitted:

In a hydraulic press, the ratio of the cross-sectional area of the large piston to that of the small piston is 50. If a force of 100 N is exerted on the small piston, the maximum force exerted by the large piston is:

The mechanical advantage (eta) of an ideal hydraulic press equals all of the following ratios EXCEPT:

The relative density (specific gravity) of a substance is defined as:

In a U-tube manometer containing two immiscible liquids in equilibrium, the heights of the liquid columns measured above the separating surface are:

Why are hydroelectric storage dams constructed with a base that is significantly thicker than the crest?

A metallic cube of side length 10 cm and density 7800 kg/m^3 is completely submerged in water (density 1000 kg/m^3). The buoyant force (upthrust) acting on the cube is (g = 10 m/s^2):

Pure water reaches its maximum density (1.000 g/cm^3 or 1000 kg/m^3) at a temperature of:

In a hydraulic press, if the radius of the large piston is 4 times that of the small piston, the mechanical advantage is:

A mercury manometer connected to a gas tank shows the mercury level in the free arm is 4 cm higher than the gas arm (Pa = 76 cm Hg). The gas pressure is:

A U-tube contains water (ρ = 1000 kg/m³) and oil (ρ = 800 kg/m³). If the oil column height above the interface is 10 cm, the balancing water column height is:

Boyle's Law states that for a fixed mass of an ideal gas kept at constant temperature, the volume V is:

Charles's Law establishes that at constant pressure, the volume of a given mass of gas is directly proportional to its:

The volume expansion coefficient at constant pressure (alpha_v) and the pressure expansion coefficient at constant volume (beta_p) for all ideal gases have the universal constant value of:

Absolute zero temperature (0 Kelvin or -273.15 °C) is defined physically as the theoretical temperature at which:

The Ideal Gas Law combining all empirical gas relationships is mathematically formulated as:

A gas cylinder contains 10 liters of gas at a pressure of 3.0 atm. If the volume is reduced to 2.5 liters at constant temperature, the new pressure inside the cylinder will be:

When a gas trapped inside a rigid container of fixed volume is heated from 27 °C (300 K) to 127 °C (400 K), its pressure increases by a factor of:

The universal gas constant R in SI units has the numerical value and dimensions of:

An air bubble released from the bottom of a deep lake expands in volume as it rises towards the surface because:

Real gases behave most closely to an ideal gas under conditions of:

A fixed quantity of an ideal gas has a volume of 600 cm^3 at 27 °C. If the gas is heated to 127 °C under constant pressure, its new volume will be:

The pressure of a gas trapped inside an incandescent light bulb is 0.8 atm at room temperature (27 °C). When the bulb operates, the filament heats the gas to 327 °C at constant volume. The operational pressure is:

If both the absolute temperature and the absolute pressure of a confined ideal gas are doubled, the volume of the gas:

The density of an ideal gas at temperature T and pressure P is rho. If the pressure is tripled and the absolute temperature is halved, the new density becomes:

The volume expansion coefficient at constant pressure (alpha_v) of an ideal gas is physically measured using:

An ionic bond is formed primarily between:

Which of the following compounds exhibits polar covalent bonding due to a significant difference in electronegativity between 0.4 and 1.7?

The nitrogen molecule (N2) contains a:

Solid ionic compounds such as crystal NaCl do NOT conduct electricity in the solid state because:

A metallic bond is physically described as the electrostatic attraction between:

Acids are chemical compounds that dissociate in aqueous solutions to produce:

The chemical formula of aluminum sulfate is correctly written as:

Which of the following oxides is classified as an amphoteric oxide that reacts with both acids and bases to yield salt and water?

The reaction between an acid and a base to produce a salt and water is known as a:

A solution with a pH value of 3.0 is classified as:

Which of the following solutions has the lowest pH value (strongest acidity) at equal concentration?

Phenolphthalein indicator cannot distinguish between an acidic solution and a neutral solution because:

Which of the following oxides is amphoteric?

According to the 2026/2027 Egyptian STEM biology syllabus, what is the exact scientific deduction regarding: Chargaff's Rules of DNA Base Pairing?

The ion directly responsible for the explosion of synaptic vesicles and the release of acetylcholine in the neuromuscular synapse cleft is:

The movement of tension in the tendrils of climbing plants such as peas and grapes depends physiologically on:

Rotational cytoplasmic movement inside living plant cells (such as Elodea plants) is indicated by:

The movement of hydrotropism in plant roots is considered tropism:

The pulling movement occurs in bulbs and corms (such as carcasses and daffodils) with the aim of:

The hormone that affects both glandular and non-glandular tissue in the adult female body is:

The hormone responsible for maintaining the balance of minerals in the blood by stimulating the reabsorption of sodium ions and eliminating excess potassium through the kidneys is:

The direct cause of myxedema in an adult is:

The gland that secretes both external ductal secretion and non-ductal hormonal secretion directly into the blood is:

A hormone secreted from the anterior lobe of the pituitary gland that stimulates the growth of Graafian follicles in the female ovary and the production of sperm in the male testicle is:

Antidiuretic hormone (ADH/vasopressin) works to raise blood pressure by:

The pituitary gland is considered the master of the endocrine glands (the maestro) because:

Which of the following hormones is considered a steroid hormone (derived from fat and cholesterol)?

The adrenal medulla is stimulated to secrete the emergency hormones adrenaline and noradrenaline via:

When severe dehydration and decreased blood volume and body fluids occur, which of the following hormonal changes occur?

The hormone that is secreted from the stomach lining and travels through the blood to return to the same stomach, stimulating it to secrete its digestive gastric juices, is:

The two hormones that are secreted from the mucous membrane of the small intestine to stimulate the pancreas to secrete its digestive juices are:

When examining a patient who suffers from severe weight loss, bulging eyes, rapid heart rate, and high temperature, the doctor diagnoses the condition as:

Beta cells in the islets of Langerhans in the pancreas are responsible for secreting the hormone:

Which of the following conditions leads to increased secretion of parathormone from the parathyroid glands?

Auxins in plants (such as indole acetic acid (IAA)) are chemicals secreted from:

Which of the following hormones is secreted by the pituitary gland and indirectly affects basic metabolic processes and the speed of oxygen consumption?

The cells that secrete the hormones oxytocin and ADH and store them in the posterior lobe of the pituitary gland are:

The salivary glands and sweat glands in the human body are examples of:

What is the direct physiological effect of injecting a healthy person with an excessive dose of the hormone insulin?

Plant hormones are responsible for the phenomenon of leaf fall and fruit ripening and falling. Where the role of a hormonal gas increases:

The lymphocytes responsible for secreting specific antibodies in humoral immunity are:

Immunoglobulin (antibody), which exists as a pentamer and contains 10 sites to bind to the antigen is:

Immune chemicals secreted by virus-infected cells to warn neighboring healthy cells to produce enzymes that inhibit virus replication.S is:

Cells that carry CD8 receptors and directly eliminate cancer cells, virus-infected cells, and transplanted organs are:

Peyer's spots's Patches) Tiny lymph nodes spread in the mucous membrane lining the:

Which of the following amino acids is considered a non-protein acid produced by plants as protective and toxic substances for microorganisms?

The chemical compound secreted by mast cells and basal white blood cells that is responsible for the widening of blood vessels and symptoms of inflammation is:

The protein secreted by cytotoxic T cells (Tc) that creates holes in the plasma membrane of the target cell is:

The cells that suppress and inhibit the immune response after eliminating the microbe and secrete lymphokine proteins are:

In the secondary immune response upon exposure to the microbe for the second time, the response is characterized as:

The covalent chemical bond that connects the heavy and light peptide chains in an antibody molecule is:

The lymphatic organ, which is called the graveyard of old and worn-out red blood cells and contains large numbers of macrophages, is:

The major histocompatibility complex (MHC) protein associates within the macrophage cell with:

Substances secreted by T helper cells (Th) and acting as a communication tool to activate neighboring B and T cells are:

The antibody that is transferred across the placenta from the blood of the pregnant mother to the blood of the fetus to give it natural, passive, acquired immunity is:

The method of action of antibodies that is considered the most appropriate and most efficient in inactivating viruses and preventing their penetration into cells is:

Complements are a group of plasma proteins that activate when an antibody binds to an antigen and work to:

Plant hypersensitivity is an effective immunological method that includes:

Natural killer (NK) cells attack and kill cancer cells and virus-infected cells by:

The surface immune receptor characteristic of T helper cells (Th) that enables them to recognize the antigen complex with the MHC protein is:

Vaccination gives humans immunity:

Injection with serum (Antiserum) containing ready-made antibodies to neutralize scorpion venom gives the patient immunity:

Which of the following immune structures represents the first line of defense in the human body to prevent the entry of pathogens?

The enzymes secreted by the plant to break down bacterial toxins and convert them into non-toxic compounds are:

Monocytes are functionally capable of leaving the bloodstream when needed:

Lymphotoxins secreted by cytotoxic T cells (Tc) eliminate the infected cell by:

The substance that the plant secretes to close wounds in its woody stems and completely isolate the affected tissue from the air and microbes is:

The phenomenon of natural parthenogenesis in honey bees results in:

Reproduction by peaceful association in two adjacent threads of the spirogyra moss (Rem al-Barak) occurs in the case of:

In the life cycle of the fougere plant (a fern), the haploid (N) gametophyte produces its male and female gametes by:

The apple is considered a false fruit from a morphological and anatomical perspective because:

Double fertilization in flowering plants involves two fusions:

The hormone that is secreted from the corpus luteum and reaches its maximum concentration on days 21 to 23 of menstruation is:

The location where fertilization of the egg by the sperm occurs in the human female reproductive system is:

The Cowper glands and the prostate gland in the male reproductive system secrete an alkaline fluid that passes into the urethra to:

The enzyme found in the apical body (Acrosome) of the sperm that helps it penetrate the compact envelope of the egg is:

Identical (monozygotic) twins arise genetically as a result of:

The umbilical cord in the human fetus contains blood vessels that are characterized by:

The contraceptive method that prevents the fertilized egg from settling in the uterine lining without hindering the ovulation or fertilization processes is:

Sertoli cells in the seminiferous tubules of the human male testicle play a functional role in:

Fructose, which is found in semen to nourish sperm outside the testicle, is secreted by:

In the life cycle of the Plasmodium malaria parasite, the human infective phase is:

The infective stage of the female Anopheles mosquito in the life cycle of Plasmodium malaria is:

Cultivation of plant tissues in a semi-natural nutrient medium (such as coconut milk) is scientific proof of:

In the human female, the second (delayed/conditional) meiotic division of the secondary oocyte takes place in:

The decomposition of the corpus luteum in the ovary of a non-pregnant woman at the end of the menstrual cycle results in:

The fetal membrane that directly surrounds the fetus and secretes a fluid that protects it from shock and dehydration and facilitates its movement is:

The outer embryonic membrane that surrounds the uterine membrane and from which digital villi emerge, which are immersed in the uterine lining to form the placenta, is:

Asexual reproduction differs from sexual reproduction in that:

Artificial parthenogenesis in flowering plants (such as the production of seedless oranges or watermelons) is carried out by:

Hydra and planaria share the ability to reproduce asexually by:

Interstitial cells in the human male testicle respond directly and secrete testosterone under the influence of a pituitary hormone:

Combined contraceptive pills are considered an effective method because they:

The maximum number of pollen grains that can be produced from the anther of a flower containing 4 sacs, each sac with 20 germinal cells (2N) is:

The motile phase (motile zygote / ookinete) in the life cycle of Plasmodium malaria is characterized by:

The number of polar bodies resulting from the maturation and fertilization of 3 primary oocytes in the ovary of a human female is equal to:

The decisive experiment for Hershey and Chase (Hershey & Chase) To prove that DNA is the genetic material of bacteriophages, I relied on:

The enzyme used in the crucial experiment to verify the experiments of Avery and his colleagues, which completely analyzes DNA and does not affect protein or RNA, is:

According to Chargaff's rules's Rules) In the DNA double helix, the equal ratio is always:

The enzyme responsible for separating the two strands of DNA from each other by breaking hydrogen bonds during replication is:

DNA polymerase always adds new nucleotides in a specific direction:

Okazaki Fragments formed on the die strip (5' to 3') During DNA replication they are joined by an enzyme:

Histone proteins responsible for shortening the length of the DNA molecule ten times and forming nucleosomes are characterized by being rich in the two basic amino acids:

If a sample of a DNA double helix contains 30% Cytosine (C), the percentage of adenine (A) bases in this sample is equal to:

The number of hydrogen bonds between the nitrogenous base pair guanine and cytosine (G - C) is:

A synthetic chromosome mutation that occurs when a piece of chromosome separates, wraps around itself at an angle of 180 degrees, and then rejoins in the same position is called:

The sequence is repeated more than one hundred thousand times in the middle of one of the chromosomes of the Drosophila insect (fruit fly) and does not code for any protein:

Telomeres are found at the ends of eukaryotic chromosomes and perform an important function in:

A segment of a DNA double helix consisting of 600 nucleotides. The number of complete turns in this segment is equal to:

DNA Repair Enzymes, which number approximately 20 enzymes, depend for their work on:

Which of the following organisms has its genetic material as a single molecule of RNA rather than DNA?

In Griffith's bacterial transformation experiment, mice died when they were injected with:

The atom in the pentose sugar molecule (dioxyribose) to which the nitrogenous base is linked by a covalent bond is:

Party 3' For a DNA strand that ends with a group:

In prokaryotic cells (such as bacteria), a single circular DNA molecule attaches to the plasma membrane at:

Common and economically beneficial chromosome duplication in the plant kingdom (such as strawberries, wheat, and apples) leads to:

A chemical substance used in the laboratory to cause mutations and chromosome duplication in the growing tips of plants is:

Mutations that are inherited to future generations and occur in reproductive cells that produce gametes are called:

The Ancon breed mutation in sheep with short, arched legs is considered a mutation:

The percentage of DNA encoding the construction of proteins and enzymes in the genetic content of eukaryotic cells (such as humans) represents approximately:

Connecting two complementary DNA strands by hydrogen bonds makes them:

The amount of DNA in a human female secondary oocyte compared to a resting somatic skin cell (before replication begins) is:

The standard start codon in an mRNA molecule recognized by the first tRNA molecule carrying methionine is:

Stop codons that bind to the release factor to terminate the translation process are:

The anticodon on the tRNA molecule carrying methionine is:

The enzyme responsible for constructing an mRNA strand from one of the two DNA strands (template strand 3' to 5') he:

The polyadenyne tail (Poly-A Tail) added to the end of the mRNA molecule in eukaryotes consists of about 200 adenine nucleotides and functionally functions to:

The enzyme that catalyzes the peptidyl transferase reaction and the formation of the peptide bond between amino acids during translation is:

Bacterial restriction endonucleases recognize specific nucleotide sequences called recognition sites, and are characterized by:

The enzyme extracted from RNA viruses and used to convert mRNA into a single strand of complementary DNA (cDNA) is:

The thermal multiplex device (PCR - Polymerase Chain Reaction) depends on an enzyme that tolerates high temperatures called:

DNA hybridization depends on the ability of single strands from different sources to combine if:

The number of codons that code for the 20 amino acids in the genetic table is equal to:

The genetic code is characterized as universal because:

Modifying enzymes produced by bacteria work to:

The first human protein produced commercially using recombinant DNA technology to treat diabetics is:

The number of amino acid molecules in a polypeptide chain resulting from mRNA translation consisting of 303 nucleotides, including the start and stop codons, is equal to:

The two main functional sites on the tRNA molecule are:

In gene cloning technology, a ligase is used to:

Polyribosome is a vital cellular structure consisting of:

In eukaryotic cells, rRNA molecules are synthesized and assembled under ribosomal subunits within:

Sticky Ends resulting from the action of shortening enzymes are characterized by:

Experiments using genes for resistance to insect pests in crop plants (such as the Bacillus thuringiensis gene) are an application to:

The two sites on the subunit of the ribosomal subunit where the two tRNA molecules stabilize during polypeptide chain elongation are:

The global scientific project that was able to decipher and arrange more than 3 billion pairs of nitrogenous bases in human cells is: