Category: Class 12 Biology Objective Questions

Biology Multiple Choice Questions on “The Male Reproductive System”.

1. Where is the male reproductive system located?
a) Pectoral region
b) Pelvis region
c) Abdominal region
d) Lumbar region
Answer: b
Clarification: The male reproductive system is located in the pelvis region. It includes a pair of testes along with accessory ducts, glands and the accessory or external genitalia.

2. _________ divides the scrotum internally.
a) Dartos tunic
b) Valves
c) Septum
d) Septum scroti
Answer: d
Clarification: Scrotum is a pouch-like loose fold of skin arising from the lower abdominal wall and hanging between the legs. Its dermis consists of a continuous layer of smooth muscle fibres called dartos tunic. A muscular partition, the septum scroti divides the scrotum internally into the right and left scrotal sacs.

3. _____ shows the external division of the scrotum.
a) Scar
b) Dartos
c) Raphe
d) Fold
Answer: c
Clarification: A muscular partition, the septum scroti divides the scrotum internally into the right and left scrotal sacs. A scar like raphe marks the position of septum externally.

4. Testes descend permanently into their respective scrotal sacs through the ______
a) inguinal canal
b) glomerulus
c) pudendal canal
d) infraorbital canal
Answer: a
Clarification: Testes develop in the abdominal cavity but during the seventh month of development, they descend permanently into their respective scrotal sacs through inguinal canals. Sometimes an inguinal canal remains open. A loop of intestine may enter the scrotum to cause a disorder, called inguinal hernia.

5. Failure of the testes to descend into the scrotum is called _______
a) palatovaginal
b) cryptorchidism
c) pudendal
d) foramen
Answer: b
Clarification: Failure of the testes to descend into the scrotum is called cryptorchidism. Palatovaginal canal is a canal present in the cranial region whereas pudendal canal is present in the pelvic region. Foramen (anatomy) means – an opening.

6. The right testes is located 1cm lower than the left testes.
a) True
b) False
Answer: b
Clarification: False, the left testes is located 1cm lower than the right testes. Testes are the primary sex organs in males. Soft, smooth, pinkish, oval bodies, about 4-5cm in length, 2-3cm in width and 2.4-2.5cm thick.

7. Testes are suspended in the scrotal sac by a ________
a) vas deferens
b) spermatic cords
c) foramens
d) urethra
Answer: b
Clarification: Testes are extra-abdominal and suspended in the scrotal sacs by spermatic cords. In elephants, whales and seals, the testes are permanently intra-abdominal.

8. Which tunicae of testes consists of a network of capillaries?
a) Tunica vaginalis
b) Tunica albuginea
c) Dartos tunic
d) Tunica vasculosa
Answer: d
Clarification: The tunica vaginalis is the outer covering of the testis. The tunica albuginea is a fibrous covering surrounding the testis is situated under the tunica vaginalis. The tunica vasculosa consists of a network of capillaries supported by delicate connective tissue which lines the tunica albuginea.

9. Where are the sperms produced?
a) Prostate gland
b) Epidermis
c) Vas deferens
d) Seminiferous tubules
Answer: d
Clarification: Each testis has about 250 compartments called testicular lobules. Each lobule contains one to three highly coiled seminiferous tubules in which sperms are produced.

10. Which cells provide nutrition to the germ cells?
a) Sertoli cells
b) Spermatogonia
c) Interstitial cells
d) Leydig cells
Answer: a
Clarification: Each seminiferous tubule is lined on its inside by two types of cells called male germ cells (spermatogonia) and a few large pyramidal Sertoli cells. The male germ cells undergo meiotic divisions finally leading to sperm formation, while Sertoli cells provide attachment and nutrition to the germ cells.

Biology Multiple Choice Questions on “Human Reproduction – Parturition and Lactation”.

1. The average duration of the gestation for humans is 9 months.
a) False
b) True
Answer: b
Clarification: The period from conception to birth of a viviparous organism is its gestation period. It varies for different organisms. It is 40 weeks approximately or 9 months for humans.

2. The act of delivering a fetus at the end of pregnancy is called ________
a) lactation
b) pregnancy
c) parturition
d) coitus
Answer: c
Clarification: Parturition, also known as childbirth, is the process in which vigorous contraction of the uterus is induced, leading to the expulsion of a fetus. It includes preparation of myometrium and cervix during pregnancy, uterine preparation, uterine contraction, and involution.

3. Vigorous contractions of the uterus during parturition are induced by ________
a) neuroendocrine mechanism
b) endocrine mechanism
c) embryo pushing out
d) uterine fluids
Answer: a
Clarification: Two major processes induce the contractions of the uterine wall during parturition. The hormones secreted from the pituitary and placenta alongside the reflexes induced by the oxytocin function to stimulate the muscle continuously. Thus this is a neuroendocrine process.

4. What is the correct sequence for parturition to occur?
a) Signal from fetus and placenta → Uterine contractions → Release of oxytocin → Rise in oxytocin secretion → Powerful contractions → Parturition
b) Uterine contractions → Release of oxytocin → Rise in oxytocin secretion → Powerful contractions → Signal from fetus and placenta → Parturition
c) Signal from fetus and placenta → Release of oxytocin → Uterine contractions → Rise in oxytocin secretion → Powerful contractions → Parturition
d) Release of oxytocin → Uterine contractions → Signal from fetus and placenta → Rise in oxytocin secretion → Powerful contractions → Parturition
Answer: c
Clarification: Parturition starts with the signal released by the fetus and the placenta. These act on the pituitary to release oxytocin. Oxytocin acts as a stimulant leading to contractions of the uterine muscles. The uterine contractions feedbacks to release more oxytocin from the pituitary. This results in more powerful contractions of the uterus until the baby is delivered in the process of parturition.

5. What is injected to induce delivery in humans?
a) Estrogen
b) Oxytocin
c) Progesterone
d) Relaxin
Answer: b
Clarification: Oxytocin is the stimulant released from anterior pituitary to increase contractions of the uterine wall. Decreased levels of oxytocin can result in the inability to push the baby out. In such scenarios, the patient is injected with intravenous oxytocin to induce uterine contractions to deliver the baby.

6. Production of milk by mammary glands of female towards the end of pregnancy is called _________
a) lactation
b) parturition
c) colostrum
d) coitus
Answer: a
Clarification: Mammary gland cells develop the potential to produce milk towards the end of pregnancy. This process is termed as lactation.

7. What is the milk produced in the initial few days of lactation called?
a) Corpus luteum
b) Colostrum
c) Corpus albicans
d) Lactum
Answer: b
Clarification: The first couple of days after the onset of lactation, the milk produced from the mammary glands is yellowish and rich in nutrients and antibodies for the newborn baby. This is called colostrum.

8. What is colostrum rich in?
a) Blood
b) Antigens
c) Antibodies
d) Life fluid
Answer: c
Clarification: The colostrum is produced by the mammary glands for the first few days after the baby is born. The purpose is to protect the baby from the antigens it will be exposed after entering the world for the first time. Hence it is enriched with antibodies.

9. Antibodies in colostrum provide new-borns with__________
a) immunity
b) long life
c) death
d) tall height
Answer: a
Clarification: The antibodies in the colostrum help the body of the baby, which has been exposed to the external world full of different antigens, the ability to fight. This is called immunity.

10. What is the period of pregnancy called?
a) Delivery
b) Menstrual cycle
c) Coitus
d) Gestation
Answer: d
Clarification: The time taken by a developing embryo inside the womb of a placental mammal is called the gestation period, at the end of which a baby is delivered in the act of parturition.

11. What is the reflex that leads to the expulsion of baby called?
a) Feet withdrawal reflex
b) Knee jerk reflex
c) Fetal ejection reflex
d) Oxytocin reflex
Answer: c
Clarification: Parturition is initiated by the fetus and the placenta. Leading to oxytocin signaling and uterine contractions. This reflex is called fetal ejection reflex.

Biology Multiple Choice Questions on “Inheritance of One Gene-1”.

1. What is the process of removal of anthers termed?
a) Demasculation
b) Emasculation
c) Remasculation
d) Masculation
Answer: b
Clarification: Emasculation is the process of removal of anthers. This is carried out to carry out pollination in a controlled manner and avoid self-pollination.

2. What process needs to be avoided for carrying of efficient crosses?
a) Self-pollination
b) Fertilization
c) Development of embryo
d) Pollen tube development
Answer: a
Clarification: Self-pollination leads to fertilization by the pollen from the same flower. A cross desires pollination and fertilization by pollen from a different plant. Hence self-pollination needs to be avoided.

3. What is the generation of plants produced by the crossing of true-breeding plants called?
a) F1
b) F0
c) F2
d) F3
Answer: a
Clarification: True-breeding plants are taken as parental plants in crosses. Hence offsprings produced by the crossing of these true-breeding plants are F1 progeny.

4. What does F in “F1 progeny” stand for?
a) Filial
b) Fillial
c) Filum
d) Filler
Answer: a
Clarification: F1 progeny refers to the first generation of offsprings. This is also termed as the first Filial generation, thereby stating their filial relationship with the true-breeding plants.

5. What should be the phenotype of the F1 progeny produced by a cross between tall and dwarf true-breeding garden pea plants?
a) Tall plants
b) Dwarf plants
c) Intermediate plants
d) Mixed population of tall and dwarf plants
Answer: a
Clarification: Tall plants are dominant over dwarf plants. Being true-breeding parents, the offsprings will all be heterozygous. Moreover, hence phenotypically, all of them will be tall.

6. I = Inflated, i = constricted. Given that the phenotype of F1 progeny is inflated pods and that the parents are true-breeding, which of the following is not a possible genotype of parents?
a) Parent 1: II; Parent 2: ii
b) Parent 1: II; Parent 2: II
c) Parent 1: ii; Parent 2: ii
d) Parent 1: ii; Parent 2: II
Answer: c
Clarification: Inflated is the dominant phenotype. Hence it can be expressed in two genotypes: II and Ii. The F1 progeny can have it in all the mentioned cases except when both parents are recessive ii.

7. What should be the phenotype of a cross between violet and white-flowered true-breeding garden pea plants?
a) Violet
b) White
c) Pink
d) Red
Answer: a
Clarification: Violet is the dominant factor over white in pea flowers. Hence violet can express even in the presence of white. The cross of violet true-breeding and white true-breeding pea plants will produce all heterozygous offsprings. Thus, all of them will have violet flowers.

8. With green pods as a dominant trait over yellow, which of the following crosses will result in all progeny having yellow pods?
a) Homozygous green and homozygous yellow
b) Heterozygous green and heterozygous green
c) Homozygous yellow and homozygous yellow
d) Homozygous green and homozygous green
Answer: c
Clarification: Yellow being recessive will express only when both alleles are present. That occurs only when both parents can contribute an allele encoding for the yellow pod. For all progeny to have yellow pods, both parents have to be homozygous for yellow pods.

9. The cross of true-breeding yellow and green seeded pea plants can only produce yellow seeded progeny.
a) True
b) False
Answer: a
Clarification: Being homozygous, these parents will produce all heterozygous individuals. Since yellow is dominant over green seed, the phenotype can be seen in the heterozygous state too. Thus, all progeny will be yellow seeded.

10. If VV produces violet flowers and vv produces white flowers, what will be the phenotype and genotype of the F1 progeny?
a) All violet; Tt
b) All white; tt
c) All violet; TT and Tt
d) All violet; TT, Tt, and tt
Answer: a
Clarification: The VV and vv upon crossing will produce all progeny with genotype Vv. This is the heterozygous state. Violet being dominant over white, all the progeny will have violet flowers.

11. The factor which expresses in homozygous and heterozygous states is called _______
a) dominant
b) recessive
c) gene
d) allele
Answer: a
Clarification: A dominant factor masks the expression of its recessive counterpart. Thus, it can express in both homozygous and heterozygous states.

12. A plant that exhibits two alleles for only one trait is called ________
a) monohybrid
b) dihybrid
c) monogamous
d) digamous
Answer: a
Clarification: Monohybrid refers to a hybrid that differs at only one gene. Thus, a plant that exhibits two alleles for one trait is a monohybrid.

13. During meiosis, what happens to the parental alleles?
a) They segregate
b) They undergo repair
c) They undergo breakage
d) They replicate
Answer: a
Clarification: Based on his studies on pea plants, he observed that the parental recessive traits were observed again only in the F2 progeny without any form of blending in F1 generation. This points out that the factors segregate or separate during the process of meiosis.

14. The presence of two different alleles at a particular locus results in _________
a) Homozygosity
b) Heterozygosity
c) Hemizygosity
d) Nullizygosity
Answer: b
Clarification: Heterozygosity refers to different alleles present at a given locus. This is the condition that is of interest to the study of genetics. It can be used to test the nature of an allele.

Biology Multiple Choice Questions on “Inheritance and Variation Principles – Sex Determination”.

1. Which of the following animals rely on environmental factors for sex determination?
a) Turtles
b) Humans
c) Grasshopper
d) Firefly
Answer: a
Clarification: Turtles are one of the organisms which rely on environmental factors for sex determination completely. They usually depend upon temperature for this purpose.

2. How is the sex of grasshopper determined?
a) Temperature
b) Pressure
c) Humidity
d) Genetically
Answer: d
Clarification: The sex of a grasshopper is determined genetically. Some experiments were carried out by some of the scientists on insects to study the genetic or chromosomal mechanism of sex determination.

3. The chromosomal basis of sex determination was discovered by which of the following scientists?
a) Stevens
b) Grey
c) Henking
d) Wilson
Answer: c
Clarification: The foundation of the chromosomal basis of sex determination was laid down by Henking in 1891. He studied a specific nuclear structure though spermatogenesis in a few insects.

4. Henking gave the term X chromosome.
a) False
b) True
Answer: a
Clarification: Henking was studying spermatogenesis in insects where he observed that only 50% of the sperms received a structure which he later termed as ‘X body’. But he could not explain the significance of this body.

5. Which of the following scientists discovered the Y-chromosome.
a) Stevens
b) Ernst Haeckel
c) Francis Crick
d) Wilson
Answer: a
Clarification: Stevens was the scientist who first discovered Y-chromosome. Many scientists concluded that the ‘X body’ which was discovered by Henking was a chromosome. Therefore, in 1905, X and Y chromosomes were named as sex chromosomes by Stevens and Wilson.

6. In which of the following organisms, the male heterogametic condition is not observed?
a) Grasshoppers
b) Humans
c) Drosophila
d) Birds
Answer: d
Clarification: Birds do not show male heterogametic conditions. Instead, they show the female heterogametic condition. Male heterogametic condition is characterised by male individuals producing two different types of gametes.

7. Which of the following determines the sex of the offspring in male heterogametic conditions?
a) Egg
b) Sperm
c) Both egg and sperm
d) It cannot be determined
Answer: b
Clarification: When the condition of male heterogamety is present, then sperm determines the sex of the offspring because two kinds of sperms are present, one with X-chromosome and the other with Y-chromosome. Eggs of an individual are the same as both of them contain 22+ X chromosomes.

8. In which of the following animals, there is a difference between the male and female numbers of chromosomes?
a) Humans
b) Drosophila
c) Grasshopper
d) Pigeon
Answer: c
Clarification: In a grasshopper, male and female individuals have a different number of chromosomes because grasshoppers exhibit XO type of male heterogamety where 2 kinds of sperms are formed- one with X-chromosome and the other with no sex chromosome.

9. Which of the following does not show XY type of male heterogametic condition?
a) Drosophila
b) Human beings
c) Elephants
d) Grasshoppers
Answer: d
Clarification: Grasshoppers do not show XY type of male heterogametic condition. XY type of male heterogametic condition is shown by a number of insects like Drosophila and mammals including human beings and elephants, the males in this type bear two types of sex chromosomes- X and Y type.

10. Y chromosome is always larger than the X-chromosome.
a) True
b) False
Answer: b
Clarification: Y-chromosome is not larger than X-chromosome, instead, it is often shorter than X-chromosome. In XY type of male heterogametic condition, both males and females have the same number of chromosomes.

11. What is the probability of having a girl child in sixth pregnancy if the first five progenies are boys?
a) 25%
b) 50%
c) 65%
d) 10%
Answer: b
Clarification: The probability of having a girl child in the sixth pregnancy, where the first five progenies were male is 50%. As humans show XY type of male heterogamety, where 50% sperms carry 22+ X chromosomes and the other 50% carry 22+Y chromosomes, therefore in each pregnancy there is 50% probability of either a male or a female child.

12. What is the full form of TDF?
a) Testis determining factor
b) Testes development factor
c) Thyroxine determining factor
d) Thyroid developing factor
Answer: a
Clarification: TDF stands for testis determining factor. TDF is essential for the development of male sex organs and if it is not produced in the body then it leads to the formation of the female sex organ.

13. The given figures show which of the following species of organisms?

a) Grasshopper
b) Butterfly
c) Moth
d) Drosophila
Answer: d
Clarification: The 1^st figure represents a male fruit fly and 2^nd figure represents a female fruit fly. Drosophila melanogaster which is used as a material for experimental genetics because it could be easily grown on a simple synthetic medium in the laboratory and a single mating produces a large number of offspring. Also, females are easily distinguishable from the males by the larger body size and the presence of an egg-laying structure.

14. Which of the following organisms does not show female heterogametic conditions?
a) Butterflies
b) Grasshopper
c) Moth
d) Birds
Answer: b
Clarification: Grasshoppers do not show female heterogametic conditions. Butterflies, moths, and birds show female heterogametic conditions where female individuals produce two different kinds of gametes.

15. In which of the following organisms, male has half the number of chromosomes than female?
a) Moths
b) Grasshoppers
c) Honey bees
d) Butterflies
Answer: c
Clarification: The female progeny of a honey bee develops from the union of a sperm and an egg whereas a male progeny develops from an unfertilised egg by the means of parthenogenesis. This means that the males have half the number of chromosomes than that of a female.

16. What kind of sex-determination system is present in honey bees?
a) Haplodiploid
b) Haploid
c) Diploid
d) XY type
Answer: a
Clarification: Honey bees exhibit a haplodiploid type of sex-determination system. This type of system has special characteristic features like the males produce sperms by mitosis. The male individuals do not have a father and thus cannot have sons, but can have a grandfather and a grandson.

Biology Multiple Choice Questions on “Evolution – Adaptive Radiation”.

1. _______ was the island where Darwin visited and discovered adaptive radiation?
a) Archipelago
b) Galapagos
c) Port Blair
d) Lakshadweep
Answer: b
Clarification: During the voyage of Darwin, he visited the Galapagos island. There, he came across different varieties of species. He saw the variations in the modification of beaks of finches.

2. Which food habit of Darwin’s finches lead to the development of many other varieties?
a) Fruiteater
b) Cactus eater
c) Insect eater
d) Seedeater
Answer: d
Clarification: It was from the seed-eating finches, many other altered forms of beak arose enabling them to be insect, cactus or fruit eaters. This led to the discovery of Adaptive radiation. Darwin’s finches are one of the best examples of this process.

3. Species which have diverged after origin from common ancestor giving rise to new species adapted to new habitats and ways of life is called as _______
a) Adaptive radiation
b) Divergent evolution
c) Convergent evolution
d) Mutation
Answer: a
Clarification: Adaptive radiation is a process that gave rise to a variety of species that originated from its original species. Darwin’s finches show adaptive radiation. They developed different beak varieties from the seed-eating variety.

4. _______ marsupials were taken as examples of adaptive radiation.
a) American
b) Australian
c) Indian
d) African
Answer: b
Clarification: Australian marsupials were taken as examples of adaptive radiation. These were the marsupials which were each different from each other but had a common ancestral stock. They were all within the Australian island continent.

5. What do we call the process when more than one adaptive radiation occurs in a single geological place?
a) Divergent evolution
b) Convergent evolution
c) Saltation
d) Overproduction
Answer: b
Clarification: Convergent evolution is the process when more than one adaptive radiation occurs in a single geological isolated area. It gives rise to analogous organs. They do not show common ancestry but they show evolution.

6. Placental mammals in Australia had similarity with the marsupials.
a) True
b) False
Answer: a
Clarification: Due to the process called adaptive radiation, placental mammals in Australia had similarity with the marsupials. It also indicates convergent evolution without common ancestry. One belongs to placental, whereas the other belongs to marsupials.

7. Lemur is a placental mammal that resembles _______ of Australian marsupials.
a) Bobcat
b) Numbat
c) Spotted cuscus
d) Flying phalanger
Answer: c
Clarification: Lemur resembles spotted cuscus. They appear to be similar because of the phenomenon called adaptive radiation. They have similar looks and appearance but does not have a common ancestral line.

8. Tasmanian wolf is an example of ________
a) Australian marsupial
b) Placental mammal
c) American marsupial
d) Placental wolves
Answer: a
Clarification: Tasmanian wolf belongs to Australian marsupial. Adaptive radiation was the process that gave rise to a variety of marsupials in Australia. They exhibit a large number of homologous organs.

9. Adaptive radiation does not confirm _______
a) Divergent evolution
b) Homology
c) Convergent evolution
d) Evolution of new forms
Answer: c
Clarification: It is not adaptive radiation that confirms convergent evolution. It is an adaptive convergence that confirms convergent evolution. The remaining options are applicable to adaptive radiation.

10. Which of the following is not an example of placental mammals?
a) Mole
b) Anteater
c) Mouse
d) Tasmanian tiger cat
Answer: d
Clarification: Tasmanian tiger cat belongs to Australian marsupials. The remaining options belong to placental mammals. The Tasmanian tiger cat resembles bobcat of placental mammals. They show convergent evolution.

11. Which of the following is a vestigial organ in animals?
a) Nictitating membrane
b) Scrotum
c) Tail
d) Eyelashes
Answer: a
Clarification: Vestigial organs are the organs which are present in reduced form and do not perform any function in the body. Here, the nictitating membrane is an example of a vestigial organ. It is a translucent membrane that forms an inner eyelid in birds, reptiles, and mammals.

Biology Interview Questions and Answers on “Bacterial Diseases in Humans-2”.

1. Which of the following is the carrier of Plague bacteria?
a) Anopheles mosquito
b) Aedes aegypti
c) Xenopsylla
d) Rhinovirus
Answer: c
Clarification: Plague spreads from rat through rat flea-Xenopsylla. They carry the pathogen Yersinia pestis. When the infected rats die, the fleas leave their body and can even bite the man and inject plague germs into his/her blood.

2. Which of the following is not a type of plague?
a) Bubonic plague
b) Septicemic plague
c) Pneumonic plague
d) Typhi plague
Answer: d
Clarification: Plague is of three basic forms- Bubonic plague is the most common type in which formation of buboes or swelling of lymph nodes occur in the neck and armpit regions. Septicemic plague causes the rupturing of blood vessels causing black patches on the skin and pneumonic plague is the only form of plague that can be transmitted from person to person.

3. What is the full form of BCG vaccine?
a) Bacteria Cold Gene
b) Bacillus Coded Gene
c) Bacillus Calmette–Guérin
d) Bacteria Coded-Guerin
Answer: c
Clarification: The full form of BCG vaccine is Bacillus Calmette–Guérin. It is an attenuated vaccine. It is commonly used for the prevention of tuberculosis disease. It is generally given between birth to six months of the baby.

4. Leprosy disease was discovered by _________
a) Hansen
b) Karl Joseph Eberth
c) Robert Koch
d) Dr Jay Levy
Answer: a
Clarification: Leprosy was first discovered by Hansen and that’s why it is commonly known as Hansen’s disease. Karl Joseph Eberth was the first person to discover typhoid, Robert Koch was the first person to discover tuberculosis and Dr Jay Levy’s group played an important role in the discovery of HIV.

5. Which medication is commonly given to treat Leprosy?
a) Ibuprofen
b) DDS (diamino-diphenyl sulphone)
c) Ciprofloxacin
d) Isotretinoin
Answer: b
Clarification: DDS (diamino-diphenyl sulphone) is commonly given to patients suffering from Leprosy. Ibuprofen is used to treat inflammation, pain and fever. Ciprofloxacin is given to patients suffering from typhoid fever and Isotretinoin is an antibiotic used to treat severe form of acne.

6. Food poisoning is commonly caused by which species of Clostridium?
a) Clostridium butyricum
b) Clostridium tetani
c) Clostridium perfringes
d) Clostridium botulinum
Answer: d
Clarification: Clostridium botulinum commonly causes food poisoning in human beings. Clostridium tetani and Clostridium perfringes cause tetanus and gangrene respectively. Clostridium butyricum is a great prebiotic for our gut and maintains the health of our brain.

7. Exotoxins are toxins released by bacteria in the medium or into the surroundings
a) True
b) False
Answer: a
Clarification: Exotoxins are toxins which are released by bacteria into the surrounding medium while Endotoxins are the toxins released by the bacteria into its own body and when it bursts, then toxins enter into the medium.

8. How many of the following diseases are caused by bacteria?

Cholera, AIDS, pneumonia, Mumps, Measles, Whooping Cough, 
typhoid, gangrene, gonorrhoea, influenza, plague, Diphtheria, 
Syphilis, Elephantiasis 

a) Five
b) Six
c) Seven
d) Eight
Answer: c
Clarification: There are seven diseases from the box caused by bacteria-Cholera is caused by Vibrio cholerae, Pneumonia is caused by Haemophilus influenzae, whooping cough is caused by Bordetella pertussis, Typhoid is caused by Salmonella typhi, Gangrene is caused by Clostridium perfringes, Plague is caused by Yersinia pestis, Diphtheria is caused by Corynebacterium diphtheria.

9. What is the first sign or symptom of tetanus?
a) Stiffness of neck
b) Swelling in neck
c) Paralysis
d) Numbness in fingers
Answer: a
Clarification: Stiffness of neck is the first symptom of Tetanus. Then there is difficulty in swallowing and chewing. Subsequently, spasms of muscles of the jaw and face take place. There is severe pain. It is often fatal disease.

10. What is the full form of ATS injection?
a) Anti Tuberculosis Serum
b) Artificial Typhoid Serum
c) Anti Tetanus Serum
d) Alpha Typhoid Sebum
Answer: c
Clarification: ATS stands for Anti Tetanus Serum injection. It should be administered within 48 hours of injury if the person has not had a tetanus shot in the past five years because Clostridium tetani enter in the blood through any wound or cut.

11. Which of the following diseases is caused by the species of Mycobacterium bacteria?
a) Typhoid and Tetanus
b) Leprosy and Tuberculosis
c) Gonorrhoea and Syphilis
d) Influenza and Leprosy
Answer: b
Clarification: Leprosy is caused by Mycobacterium leprae bacterium and tuberculosis is caused by Mycobacterium tuberculosis bacterium.

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