General Science Questions (MCQs) for Competitive Examinations
General Science Multiple choice questions for GK paper in SSC, NDA, CDS, UPSC, UPPSC and State PSC Examinations. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
1. The exceptionally low melting point of mercury can be explained on the basis of which of the following explanations?
1. Mercury has completely filled-up atomic orbitals
2. In mercury, the binding energy of outer electrons (towards nucleus) is highest and no electron is available to participate in metallic bond formation
Choose the correct option from the codes given below:
[A] Only 1 is correct
[B] Only 2 is correct
[C] Both 1 & 2 are correct
[D] Neither 1 nor 2 is correct
Show Answer
Correct Answer: C [ Both 1 & 2 are correct]
Notes:
Mercury belongs to the zinc group of elements in the periodic table, which comprises zinc, cadmium and mercury. They all have completely filled-up atomic orbitals. It becomes difficult to knock out these electron(s) from their orbitals and form metallic bonds. With its filled shell electron configuration it is very reluctant to form bonds even with other mercury atoms.
2. Heart attack occurs due to
____:
[A] Impairment of hearts working due to unknown reasons
[B] Bacterial attack on the heart
[C] Lack of supply of blood to the heart itself
[D] Stopping of heart beat
Show Answer
Correct Answer: C [Lack of supply of blood to the heart itself]
Notes:
A heart attack occurs when blood flow to a part of your heart is blocked for a long enough time that part of the heart muscle is damaged or dies. The medical term for this is myocardial infarction. Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. If the blood flow is blocked, the heart is starved of oxygen and heart cells die.
3. Carbon monoxide poisoning can be cured by
____:
[A] Drinking lemon-water
[B] Eating butter
[C] Exposing the affected person to fresh oxygen
[D] Consuming multi-vitamin tablet
Show Answer
Correct Answer: C [Exposing the affected person to fresh oxygen]
Notes:
Carbon monoxide poisoning can be cured by exposing the affected person to fresh oxygen. It is because CO posoning leads to oxygen starvation of body cells. This therapy involves breathing pure oxygen in a chamber in which the air pressure is about two to three times higher than normal. This speeds the replacement of carbon monoxide with oxygen in your blood. Hyperbaric oxygen therapy may be used in cases of severe carbon monoxide poisoning.
4. Root cap is derived from
____:
[A] Dermatogen
[B] Calyptrogen
[C] Protoderm
[D] Histogen
Show Answer
Correct Answer: B [Calyptrogen]
Notes:
Calyptrogen is a layer of rapidly dividing cells at the tip of a plant root, from which the root cap is formed. It occurs in grasses and many other plants. The root cap is formed by several layers of cells that envelop the root tip externally. This covering of cells, of which the outermost ones are dead, envelops and protects the growing tip of root.
5. Which of the following brings back deoxygenated blood from different parts of human body to heart?
[A] Veins
[B] Arteries
[C] Nerves
[D] Lungs
Show Answer
Correct Answer: A [Veins]
Notes:
Veins carry the deoxygenated blood from different parts of the body to the heart. There are two main veins that carry out this job. The superior vena cava carries deoxygenated blood from head, neck, thorax and hands to the right atrium of our heart. The inferior vena cava carries deoxygenated blood from legs, pelvic region and abdominal organs to the right atrium of our heart. Among the veins, only pulmonary vein carries oxygenated blood.
6. In male sharks, Claspers are found attached to
____:
[A] Anal fin
[B] Ventral fin
[C] Pectoral fin
[D] Pelvic fin
Show Answer
Correct Answer: D [Pelvic fin]
Notes:
Claspers are organs found in male elasmobranchs. Each male has two claspers. They are located along the inner side of the shark or ray’s pelvic fin and are used in reproduction. During mating, the male deposits his sperm into the female’s cloaca (the opening that serves as the entrance to the uterus, intestine and urinary tract) via grooves that lie in the upper side of the claspers.
7. Protein part of enzyme is known as ____:
[A] Isoenzyme
[B] Holoenzyme
[C] Apoenzyme
[D] All of the above
Show Answer
Correct Answer: C [Apoenzyme]
Notes:
Enzymes are defined as biological catalysts. Chemically all enzymes are globular proteins. Each enzyme catalyses only one chemical reaction. Protein part of enzyme is known as Apoenzyme. It forms an active enzyme system by combination with a coenzyme and determines the specificity of this system for a substrate.
8. Growing agricultural crops between rows of planted trees is known as ____:
[A] Jhum
[B] Agro forestry
[C] Social forestry
[D] Taungya system
Show Answer
Correct Answer: D [Taungya system]
Notes:
The Taungya system involves growing agricultural crops between rows of planted trees (sal, teak, etc). Along with jhum cultivation, it is one of the well-known systems of agro forestry programmes in practice in our country.
9. Synapse gap is present between which of the following?
[A] Two Kidneys
[B] Two neurons
[C] Brain and Spinal Cord
[D] None of the above
Show Answer
Correct Answer: B [Two neurons]
Notes:
The gap between the two neurons is called the synapse. It is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron. Synapses are essential to neuronal function : neurons are cells that are specialized to pass signals to individual target cells, and synapses are the means by which they do so.
10. Dumb-bell shaped guard cells are present in
____:
[A] Mango
[B] Wheat
[C] Gram
[D] Groundnut
Show Answer
Correct Answer: B [Wheat]
Notes:
Monocost and dicots differ in the location of stomata and shape of guard cells. In monocots stomata are Dumb-bell shaped in dicots they are bean-shaped.
