BiologyQ51–100 of 177 questions
Page 2 of 3 · English
51
BiologyMediumMCQAIPMT · 1992
The hindbrain consists of:
A
Pons + cerebellum
B
Hypothalamus + cerebellum
C
Medulla oblongata + cerebellum
D
Medulla oblongata + cerebellum + pons
Solution
(D) The hindbrain is composed of three main parts:
$1$. Pons: $A$ structure that acts as a bridge between different parts of the brain.
$2$. Cerebellum: Responsible for maintaining balance and posture.
$3$. Medulla oblongata: Controls involuntary functions like respiration,cardiovascular reflexes,and gastric secretions.
Therefore,the hindbrain consists of the pons,cerebellum,and medulla oblongata.
$1$. Pons: $A$ structure that acts as a bridge between different parts of the brain.
$2$. Cerebellum: Responsible for maintaining balance and posture.
$3$. Medulla oblongata: Controls involuntary functions like respiration,cardiovascular reflexes,and gastric secretions.
Therefore,the hindbrain consists of the pons,cerebellum,and medulla oblongata.
0 likesView Solution
52
BiologyEasyMCQAIPMT · 1992
Foramen of Monro is an aperture between
A
$2$nd and $3$rd ventricle
B
Diocoel and metacoel
C
Rhinocoel and diocoel
D
$3$rd and $4$th ventricle
Solution
(A) The Foramen of Monro,also known as the interventricular foramen,is a channel that connects the paired lateral ventricles ($1$st and $2$nd ventricles) to the third ventricle ($3$rd ventricle) in the brain. Therefore,it serves as an aperture between the $2$nd and $3$rd ventricles.
0 likesView Solution
53
BiologyEasyMCQAIPMT · 1992
Which of the following hormones act as neurotransmitters?
A
Acetylcholine and secretin
B
Cholecystokinin and acetylcholine
C
Adrenaline and acetylcholine
D
Cholecystokinin and adrenaline
Solution
(C) The correct answer is $C$.
Nerve impulses are transmitted across the synapse from the axon terminal to the dendrite of the next neuron with the help of chemical substances known as neurotransmitters.
$Acetylcholine$ and $Adrenaline$ (also known as $Epinephrine$) are well-known examples of neurotransmitters produced by the secretory vesicles located in the synaptic knobs of neurons.
Nerve impulses are transmitted across the synapse from the axon terminal to the dendrite of the next neuron with the help of chemical substances known as neurotransmitters.
$Acetylcholine$ and $Adrenaline$ (also known as $Epinephrine$) are well-known examples of neurotransmitters produced by the secretory vesicles located in the synaptic knobs of neurons.
0 likesView Solution
54
BiologyMediumMCQAIPMT · 1992
Afferent nerve fibres carry impulses from
A
Effector organs to central nervous system
B
Receptors to central nervous system
C
Central nervous system to muscles
D
Central nervous system to receptors
Solution
(B) The peripheral nervous system is divided into two types of nerve fibres: afferent and efferent.
Afferent nerve fibres transmit impulses from tissues or organs (receptors) to the central nervous system $(CNS)$.
Efferent nerve fibres transmit regulatory impulses from the central nervous system to the concerned peripheral tissues or organs (effectors).
Therefore,the correct option is $B$.
Afferent nerve fibres transmit impulses from tissues or organs (receptors) to the central nervous system $(CNS)$.
Efferent nerve fibres transmit regulatory impulses from the central nervous system to the concerned peripheral tissues or organs (effectors).
Therefore,the correct option is $B$.
0 likesView Solution
55
BiologyMediumMCQAIPMT · 1992
Columella auris is a modified
A
Articular
B
Sphenethmoid
C
Hyomandibular
D
Quadrate
Solution
(C) The $Columella$ $auris$ is a bone found in the middle ear of amphibians, reptiles, and birds.
It is a modified $Hyomandibular$ bone, which is derived from the dorsal end of the hyoid arch.
In mammals, this same structure is homologous to the $Stapes$ bone.
It is a modified $Hyomandibular$ bone, which is derived from the dorsal end of the hyoid arch.
In mammals, this same structure is homologous to the $Stapes$ bone.
0 likesView Solution
56
BiologyEasyMCQAIPMT · 1992
The Vagus nerve is:
A
Spinal nerve
B
Sympathetic nerve
C
$X$ cranial nerve
D
Parasympathetic nerve
Solution
(C) The Vagus nerve is the $10th$ $(X)$ cranial nerve.
It originates from the sides of the medulla oblongata.
It is a mixed nerve containing both sensory and motor fibers and serves as a major component of the parasympathetic nervous system.
It originates from the sides of the medulla oblongata.
It is a mixed nerve containing both sensory and motor fibers and serves as a major component of the parasympathetic nervous system.
0 likesView Solution
57
BiologyMediumMCQAIPMT · 1992
Calcitonin lowers the calcium level in the blood. This is secreted by
A
Parathyroid
B
Hypothalamus
C
Adrenal
D
Thyroid
Solution
(D) Calcitonin is a peptide hormone that plays a crucial role in calcium homeostasis by lowering blood calcium levels.
It is secreted by the parafollicular cells,also known as $C$-cells,which are located within the thyroid gland.
It is secreted by the parafollicular cells,also known as $C$-cells,which are located within the thyroid gland.
0 likesView Solution
58
BiologyMediumMCQAIPMT · 1992
Angiotensin is derived from the plasma protein $angiotensinogen$ by the action of renin and other stimuli. Angiotensin stimulates which of the following glands?
A
Thyroid
B
Adrenal
C
Ovary
D
Thymus
Solution
(B) The $Renin-Angiotensin-Aldosterone$ System $(RAAS)$ is a critical mechanism for regulating blood pressure and fluid balance.
$1$. When blood pressure or sodium levels decrease,the kidneys release the enzyme $renin$.
$2$. $Renin$ converts the plasma protein $angiotensinogen$ into $angiotensin-I$,which is subsequently converted to $angiotensin-II$ by $Angiotensin-Converting$ $Enzyme$ $(ACE)$.
$3$. $Angiotensin-II$ acts on the $adrenal$ $cortex$ (specifically the $zona$ $glomerulosa$) to stimulate the secretion of the hormone $aldosterone$.
$4$. $Aldosterone$ increases the reabsorption of sodium and water in the kidneys,thereby increasing blood volume and blood pressure.
$1$. When blood pressure or sodium levels decrease,the kidneys release the enzyme $renin$.
$2$. $Renin$ converts the plasma protein $angiotensinogen$ into $angiotensin-I$,which is subsequently converted to $angiotensin-II$ by $Angiotensin-Converting$ $Enzyme$ $(ACE)$.
$3$. $Angiotensin-II$ acts on the $adrenal$ $cortex$ (specifically the $zona$ $glomerulosa$) to stimulate the secretion of the hormone $aldosterone$.
$4$. $Aldosterone$ increases the reabsorption of sodium and water in the kidneys,thereby increasing blood volume and blood pressure.
0 likesView Solution
59
BiologyEasyMCQAIPMT · 1992
Which of the following serves as an indicator of atmospheric pollution?
A
Ferns
B
Liverworts
C
Hornworts
D
Epiphytic lichens
Solution
(D) The correct answer is $D$. Lichens are highly sensitive to atmospheric pollutants,particularly sulfur dioxide $(SO_2)$. They do not grow in areas with high levels of air pollution,making them excellent bioindicators for monitoring air quality.
0 likesView Solution
60
BiologyMediumMCQAIPMT · 1992
Alternation of generations is not observed in bacteria because they lack:
A
Syngamy and meiosis.
B
Distinct chromosomes.
C
Syngamy.
D
Genetic recombination.
Solution
(A) Alternation of generations involves the regular alternation between a haploid $(n)$ gametophyte phase and a diploid $(2n)$ sporophyte phase. This process requires the occurrence of syngamy (fusion of gametes) to restore the diploid state and meiosis (reduction division) to return to the haploid state. Bacteria are prokaryotic organisms that reproduce primarily through binary fission. They do not undergo true sexual reproduction involving the formation of gametes (syngamy) or reduction division (meiosis). Therefore,they cannot exhibit an alternation of generations.
0 likesView Solution
61
BiologyMediumMCQAIPMT · 1992
Lichens are indicators of $SO_2$ pollution because they are ........
A
symbiotic associations of algae and fungi.
B
growing faster than others.
C
sensitive to $SO_2$.
D
flourishing in $SO_2$ rich environments.
Solution
(C) Lichens are composite organisms consisting of a symbiotic association between algae (phycobiont) and fungi (mycobiont).
They are well-known as biological indicators of air pollution,specifically sulfur dioxide $(SO_2)$.
Lichens are highly sensitive to $SO_2$ and cannot grow in areas where the concentration of $SO_2$ is high.
Therefore,their absence in a particular area serves as an indicator of $SO_2$ pollution.
They are well-known as biological indicators of air pollution,specifically sulfur dioxide $(SO_2)$.
Lichens are highly sensitive to $SO_2$ and cannot grow in areas where the concentration of $SO_2$ is high.
Therefore,their absence in a particular area serves as an indicator of $SO_2$ pollution.
0 likesView Solution
62
BiologyEasyMCQAIPMT · 1992
Resin and turpentine are obtained from $..........$.
A
$Cycas$
B
$Pinus$
C
$Cedrus$
D
$Abies$
Solution
(B) Resin and turpentine are commercially important products obtained from the genus $Pinus$ (pine trees).
$Pinus$ species are gymnosperms that produce resin in their resin ducts.
Turpentine is obtained by the distillation of resin collected from these trees.
Therefore,the correct option is $B$.
$Pinus$ species are gymnosperms that produce resin in their resin ducts.
Turpentine is obtained by the distillation of resin collected from these trees.
Therefore,the correct option is $B$.
0 likesView Solution
63
BiologyMediumMCQAIPMT · 1992
If the pollen grain of $Pinus$ contains $6$ chromosomes,then how many chromosomes will its endosperm have?
A
$12$
B
$1$
C
$6$
D
$24$
Solution
(C) In $Pinus$ (a gymnosperm),the pollen grain represents the male gametophyte,which is haploid $(n)$.
Given that the pollen grain has $6$ chromosomes,the haploid number $(n)$ is $6$.
The endosperm in gymnosperms is a haploid tissue $(n)$ formed before fertilization.
Therefore,the number of chromosomes in the endosperm will be equal to the haploid number $(n)$,which is $6$.
Given that the pollen grain has $6$ chromosomes,the haploid number $(n)$ is $6$.
The endosperm in gymnosperms is a haploid tissue $(n)$ formed before fertilization.
Therefore,the number of chromosomes in the endosperm will be equal to the haploid number $(n)$,which is $6$.
0 likesView Solution
64
BiologyMediumMCQAIPMT · 1992
In which of the following plants is the sporophytic generation represented only by the zygote?
A
Pinus
B
Selaginella
C
Chlamydomonas
D
Dryopteris
Solution
(C) In $Chlamydomonas$, the life cycle is haplontic.
In a haplontic life cycle, the dominant, photosynthetic phase is the free-living gametophyte $(n)$.
The sporophyte generation $(2n)$ is represented only by the single-celled zygote, which undergoes meiosis to produce haploid spores.
$Pinus$ (gymnosperm), $Selaginella$ (pteridophyte), and $Dryopteris$ (pteridophyte) exhibit diplontic or haplo-diplontic life cycles where the sporophyte is the dominant, multicellular phase.
In a haplontic life cycle, the dominant, photosynthetic phase is the free-living gametophyte $(n)$.
The sporophyte generation $(2n)$ is represented only by the single-celled zygote, which undergoes meiosis to produce haploid spores.
$Pinus$ (gymnosperm), $Selaginella$ (pteridophyte), and $Dryopteris$ (pteridophyte) exhibit diplontic or haplo-diplontic life cycles where the sporophyte is the dominant, multicellular phase.
0 likesView Solution
65
BiologyMediumMCQAIPMT · 1992
Which of the following is $NOT$ common between $Funaria$ and $Selaginella$?
A
Archegonia
B
Embryo
C
Flagellated sperms
D
Roots
Solution
(D) $Funaria$ is a bryophyte,while $Selaginella$ is a pteridophyte.
$Funaria$ lacks true roots and instead possesses rhizoids.
In contrast,$Selaginella$ possesses true roots,stems,and leaves.
Therefore,'roots' are not common between the two.
$Funaria$ lacks true roots and instead possesses rhizoids.
In contrast,$Selaginella$ possesses true roots,stems,and leaves.
Therefore,'roots' are not common between the two.
0 likesView Solution
66
BiologyMediumMCQAIPMT · 1992
Plants that lack flowers and fruits but produce seeds are known as . . . . . . .
A
Pteridophytes
B
Algae
C
Ferns
D
Gymnosperms
Solution
(D) Gymnosperms are plants in which the ovules are not enclosed by any ovary wall and remain exposed,both before and after fertilization.
Since they lack an ovary,they do not produce flowers or fruits.
However,they produce seeds,which are naked (not enclosed in a fruit).
Therefore,they are referred to as 'naked-seeded' plants.
Since they lack an ovary,they do not produce flowers or fruits.
However,they produce seeds,which are naked (not enclosed in a fruit).
Therefore,they are referred to as 'naked-seeded' plants.
0 likesView Solution
67
BiologyMediumMCQAIPMT · 1992
Which plant group is characterized by the presence of spores and embryos but lacks vascular tissues and seeds?
A
Pteridophytes
B
Rhodophyta
C
Bryophytes
D
Phaeophyta
Solution
(C) The plant group that produces spores and embryos but lacks vascular tissues ($xylem$ and $phloem$) and seeds is known as $Bryophytes$.
$1$. $Bryophytes$ are often called the amphibians of the plant kingdom.
$2$. They possess a multicellular embryo stage in their life cycle.
$3$. They reproduce via spores.
$4$. Unlike $Pteridophytes$, $Gymnosperms$, and $Angiosperms$, they do not have specialized vascular tissues for the conduction of water and nutrients.
$1$. $Bryophytes$ are often called the amphibians of the plant kingdom.
$2$. They possess a multicellular embryo stage in their life cycle.
$3$. They reproduce via spores.
$4$. Unlike $Pteridophytes$, $Gymnosperms$, and $Angiosperms$, they do not have specialized vascular tissues for the conduction of water and nutrients.
0 likesView Solution
68
BiologyEasyMCQAIPMT · 1992
The larva of $Ascaris$ is known as:
A
$Cysticercus$
B
$Rhabditiform$
C
$Hexacanth$
D
$Oncosphere$
Solution
(B) The life cycle of $Ascaris$ $lumbricoides$ involves a larval stage that hatches from the egg. This specific larval stage is known as the $Rhabditiform$ larva. It is the first-stage larva that is infective to the host after undergoing further development within the egg.
0 likesView Solution
69
BiologyEasyMCQAIPMT · 1992
The voice box of birds is known as $..........$.
A
Pygostyle
B
Larynx
C
Syrinx
D
Synsacrum
Solution
(C) The voice box of birds is called the $Syrinx$.
It is a specialized vocal organ located at the base of the trachea in birds.
Unlike mammals,which use the $Larynx$ to produce sound,birds use the $Syrinx$ to generate complex vocalizations and songs.
It is a specialized vocal organ located at the base of the trachea in birds.
Unlike mammals,which use the $Larynx$ to produce sound,birds use the $Syrinx$ to generate complex vocalizations and songs.
0 likesView Solution
70
BiologyEasyMCQAIPMT · 1992
Which of the following is an oviparous mammal?
A
Kangaroo
B
Platypus
C
Koala
D
Whale
Solution
(B) Mammals are generally viviparous,meaning they give birth to live young. However,there is a small group of mammals known as monotremes that lay eggs. The $Ornithorhynchus$ (Platypus) and $Tachyglossus$ (Echidna) are examples of oviparous mammals. Therefore,the correct option is $B$.
0 likesView Solution
71
BiologyEasyMCQAIPMT · 1992
The Indian bullfrog is $..........$.
A
Rana tigrina
B
$R$. sylvatica
C
$R$. catesbeiana
D
$R$. esculenta
Solution
(A) The scientific name of the Indian bullfrog is $Rana \ tigrina$.
It is a species of frog found in India and other parts of South Asia.
$Rana \ catesbeiana$ is the American bullfrog,while $Rana \ sylvatica$ is the wood frog.
It is a species of frog found in India and other parts of South Asia.
$Rana \ catesbeiana$ is the American bullfrog,while $Rana \ sylvatica$ is the wood frog.
0 likesView Solution
72
BiologyEasyMCQAIPMT · 1992
Which is the simplest canal system in Porifera?
A
Ascon type
B
Leucon type
C
Sycon type
D
Radial type
Solution
(A) The canal system in Porifera (sponges) is a characteristic feature that facilitates water circulation for feeding,respiration,and excretion.
There are three main types of canal systems:
$1$. $Ascon$ type: This is the simplest type of canal system,found in sponges like $Leucosolenia$. In this system,water enters through ostia directly into the spongocoel and exits through the osculum.
$2$. $Sycon$ type: This is more complex than the $Ascon$ type,involving radial canals.
$3$. $Leucon$ type: This is the most complex type of canal system,characterized by flagellated chambers.
Therefore,the $Ascon$ type is the simplest.
There are three main types of canal systems:
$1$. $Ascon$ type: This is the simplest type of canal system,found in sponges like $Leucosolenia$. In this system,water enters through ostia directly into the spongocoel and exits through the osculum.
$2$. $Sycon$ type: This is more complex than the $Ascon$ type,involving radial canals.
$3$. $Leucon$ type: This is the most complex type of canal system,characterized by flagellated chambers.
Therefore,the $Ascon$ type is the simplest.
0 likesView Solution
73
BiologyMediumMCQAIPMT · 1992
Starfish belongs to the class:
A
Asteroidea
B
Ophiuroidea
C
Holothuroidea
D
Crinoidea
Solution
(A) The phylum $Echinodermata$ is divided into several classes based on their body structure and symmetry.
Starfish,also known as sea stars,belong to the class $Asteroidea$.
Members of this class are characterized by a central disc with five or more arms radiating from it.
$Ophiuroidea$ includes brittle stars,$Holothuroidea$ includes sea cucumbers,and $Crinoidea$ includes sea lilies.
Starfish,also known as sea stars,belong to the class $Asteroidea$.
Members of this class are characterized by a central disc with five or more arms radiating from it.
$Ophiuroidea$ includes brittle stars,$Holothuroidea$ includes sea cucumbers,and $Crinoidea$ includes sea lilies.
0 likesView Solution
74
BiologyMediumMCQAIPMT · 1992
The eye of which mollusc group resembles the vertebrate eye?
A
Bivalvia
B
Gastropoda
C
Pelecypoda
D
Cephalopoda
Solution
(D) The members of the class $Cephalopoda$ (e.g.,octopus,squid) possess complex,camera-type eyes that are remarkably similar in structure and function to the vertebrate eye. Both types of eyes feature a lens,iris,and retina,representing a classic example of convergent evolution.
0 likesView Solution
75
BiologyEasyMCQAIPMT · 1992
Aristotle's lantern is found in the class .......... .
A
Echinoidea
B
Asteroidea
C
Holothuroidea
D
Ophiuroidea
Solution
(A) Aristotle's lantern is a specialized chewing apparatus found in sea urchins,which belong to the class $Echinoidea$ of the phylum $Echinodermata$.
It consists of five hard,calcareous teeth that are used to scrape algae and other food materials from rocks.
Therefore,the correct option is $A$.
It consists of five hard,calcareous teeth that are used to scrape algae and other food materials from rocks.
Therefore,the correct option is $A$.
0 likesView Solution
76
BiologyMediumMCQAIPMT · 1992
Statement $-A:$ $Periplaneta$ $americana$ is a nocturnal,omnivorous,and household pest.
Reason $-R:$ It acts as a scavenger.
Reason $-R:$ It acts as a scavenger.
A
$A$ is true,$R$ is false.
B
$A$ is false,$R$ is true.
C
Both $A$ and $R$ are true,and $R$ is the correct explanation of $A$.
D
Both $A$ and $R$ are true,but $R$ is not the correct explanation of $A$.
Solution
(C) Statement $-A$ is true because $Periplaneta$ $americana$ (cockroach) is indeed a nocturnal,omnivorous,and household pest that causes damage to food and contaminates it.
Reason $-R$ is also true because cockroaches are scavengers,meaning they feed on decaying organic matter,waste,and food scraps.
Since the cockroach's habit of being a scavenger is the primary reason it thrives as a household pest (by feeding on human waste and food),$R$ is the correct explanation of $A$.
Reason $-R$ is also true because cockroaches are scavengers,meaning they feed on decaying organic matter,waste,and food scraps.
Since the cockroach's habit of being a scavenger is the primary reason it thrives as a household pest (by feeding on human waste and food),$R$ is the correct explanation of $A$.
0 likesView Solution
77
BiologyMediumMCQAIPMT · 1992
Which of the following is true for $Taenia$?
A
Male organs develop in posterior proglottids.
B
Male organs develop in anterior proglottids.
C
Female organs develop in anterior proglottids.
D
Mature proglottids contain both male and female organs.
Solution
(D) $Taenia$ (tapeworm) is a hermaphrodite organism.
In its life cycle,the proglottids are segments that mature as they move away from the scolex (anterior end).
The anterior proglottids are immature.
The middle proglottids are mature and contain both male and female reproductive organs (hermaphroditic).
The posterior proglottids are gravid,containing fertilized eggs.
Therefore,the mature proglottids contain both male and female reproductive organs.
In its life cycle,the proglottids are segments that mature as they move away from the scolex (anterior end).
The anterior proglottids are immature.
The middle proglottids are mature and contain both male and female reproductive organs (hermaphroditic).
The posterior proglottids are gravid,containing fertilized eggs.
Therefore,the mature proglottids contain both male and female reproductive organs.
0 likesView Solution
78
BiologyMediumMCQAIPMT · 1992
The floral formula of Tomato/Tobacco is ......
A
$\bigoplus \text{ } K_{4-5} C_{1+2+(2)} A_{10} G_{(2)}$
B
$\bigoplus \text{ } K_{2+2} C_4 A_{2+4} G_1$
C
$\bigoplus \text{ } P_2 A_3 G_1$
D
$\bigoplus \text{ } K_{(5)} C_{(5)} A_5 G_{(2)}$
Solution
(D) Tomato and Tobacco belong to the family $Solanaceae$.
The floral formula for the family $Solanaceae$ is represented as: $\bigoplus \text{ } K_{(5)} C_{(5)} A_5 G_{(2)}$.
- $\bigoplus$: Actinomorphic (radial symmetry).
- $K_{(5)}$: Calyx with $5$ sepals,gamosepalous (fused).
- $C_{(5)}$: Corolla with $5$ petals,gamopetalous (fused).
- $A_5$: Androecium with $5$ stamens,epipetalous.
- $G_{(2)}$: Gynoecium with $2$ carpels,syncarpous (fused),superior ovary.
The floral formula for the family $Solanaceae$ is represented as: $\bigoplus \text{ } K_{(5)} C_{(5)} A_5 G_{(2)}$.
- $\bigoplus$: Actinomorphic (radial symmetry).
- $K_{(5)}$: Calyx with $5$ sepals,gamosepalous (fused).
- $C_{(5)}$: Corolla with $5$ petals,gamopetalous (fused).
- $A_5$: Androecium with $5$ stamens,epipetalous.
- $G_{(2)}$: Gynoecium with $2$ carpels,syncarpous (fused),superior ovary.
0 likesView Solution
79
BiologyDifficultMCQAIPMT · 1992
Vivipary means ...... .
A
Germination of seeds from hypogeal cotyledons
B
Germination of seeds from epigeal cotyledons
C
Development of fruit without pollination
D
Germination of seeds inside the fruit while still attached to the parent plant
Solution
(D) Vivipary is a phenomenon where seeds germinate while still attached to the parent plant.
This is a common adaptation in plants growing in saline marshes or mangroves (e.g.,$Rhizophora$ and $Avicennia$).
In these environments,the seeds would not be able to germinate if they fell into the salty water,so the embryo grows into a seedling while attached to the parent,eventually dropping into the mud to establish itself.
This is a common adaptation in plants growing in saline marshes or mangroves (e.g.,$Rhizophora$ and $Avicennia$).
In these environments,the seeds would not be able to germinate if they fell into the salty water,so the embryo grows into a seedling while attached to the parent,eventually dropping into the mud to establish itself.
0 likesView Solution
80
BiologyMediumMCQAIPMT · 1992
The vascular cambium produces . . . . . . .
A
Primary xylem and primary phloem
B
Secondary xylem and secondary phloem
C
Primary xylem and secondary phloem
D
Secondary xylem and primary phloem
Solution
(B) The vascular cambium is a lateral meristem that is responsible for secondary growth in dicotyledonous plants.
During secondary growth,the cells of the vascular cambium divide periclinally.
The cells produced towards the inner side differentiate into secondary xylem,while the cells produced towards the outer side differentiate into secondary phloem.
Therefore,the vascular cambium produces secondary xylem and secondary phloem.
During secondary growth,the cells of the vascular cambium divide periclinally.
The cells produced towards the inner side differentiate into secondary xylem,while the cells produced towards the outer side differentiate into secondary phloem.
Therefore,the vascular cambium produces secondary xylem and secondary phloem.
0 likesView Solution
81
BiologyMediumMCQAIPMT · 1992
The characteristic feature of a bicollateral vascular bundle is ............ .
A
Phloem is present on both sides of the xylem.
B
Transverse division of the vascular bundle.
C
Longitudinal division of the vascular bundle.
D
Xylem is sandwiched between phloem tissues.
Solution
(A) bicollateral vascular bundle is a type of conjoint vascular bundle where the phloem is present on both the outer and inner sides of the xylem.
This means the xylem is sandwiched between two layers of phloem.
This arrangement is commonly found in the stems of plants belonging to the family $Cucurbitaceae$.
This means the xylem is sandwiched between two layers of phloem.
This arrangement is commonly found in the stems of plants belonging to the family $Cucurbitaceae$.
0 likesView Solution
82
BiologyEasyMCQAIPMT · 1992
The blood components required for the production of antibodies are . . . . . . .
A
Platelets
B
Monocytes
C
Red blood cells
D
Lymphocytes
Solution
(D) Antibodies are specialized proteins produced by the immune system to identify and neutralize foreign pathogens like bacteria and viruses.
In the human body,$B$-lymphocytes are the specific type of white blood cells responsible for the production of antibodies.
When these cells encounter an antigen,they differentiate into plasma cells,which secrete large quantities of antibodies into the blood and lymph.
Therefore,the correct answer is $D$ (Lymphocytes).
In the human body,$B$-lymphocytes are the specific type of white blood cells responsible for the production of antibodies.
When these cells encounter an antigen,they differentiate into plasma cells,which secrete large quantities of antibodies into the blood and lymph.
Therefore,the correct answer is $D$ (Lymphocytes).
0 likesView Solution
83
BiologyMediumMCQAIPMT · 1992
An electron microscope has a higher resolving power than a light microscope. This is due to:
A
The use of electromagnetic lenses.
B
The very short wavelength of the electron beam.
C
The use of a light source with a short wavelength.
D
The use of glass lenses with a high numerical aperture.
Solution
(B) The resolving power of a microscope is inversely proportional to the wavelength of the radiation used for illumination $(Resolving Power \propto 1/\lambda)$.
Visible light has a relatively long wavelength,limiting the resolution of light microscopes.
In contrast,electron beams behave like waves with extremely short wavelengths (much smaller than visible light).
Because the wavelength of an electron beam is significantly shorter,the electron microscope can resolve much smaller details,resulting in a much higher resolving power.
Visible light has a relatively long wavelength,limiting the resolution of light microscopes.
In contrast,electron beams behave like waves with extremely short wavelengths (much smaller than visible light).
Because the wavelength of an electron beam is significantly shorter,the electron microscope can resolve much smaller details,resulting in a much higher resolving power.
0 likesView Solution
84
BiologyMediumMCQAIPMT · 1992
Hammerling's experiment on $Acetabularia$ proved the role of:
A
Cytoplasm in differentiation
B
Nucleus in heredity
C
Chromosomes in heredity
D
Nucleus/cytoplasmic ratio
Solution
(B) Joachim Hammerling conducted experiments on the unicellular green alga $Acetabularia$ to determine the role of the nucleus in heredity.
He used two species,$Acetabularia$ $crenulata$ and $Acetabularia$ $mediterranea$.
By performing grafting experiments,he observed that the cap morphology (the shape of the umbrella-like structure) was determined by the nucleus present in the rhizoid.
When the nucleus of one species was transplanted into the stalk of another,the regenerated cap always resembled the species from which the nucleus was derived.
This proved that the nucleus contains the genetic information responsible for controlling cellular traits and heredity.
He used two species,$Acetabularia$ $crenulata$ and $Acetabularia$ $mediterranea$.
By performing grafting experiments,he observed that the cap morphology (the shape of the umbrella-like structure) was determined by the nucleus present in the rhizoid.
When the nucleus of one species was transplanted into the stalk of another,the regenerated cap always resembled the species from which the nucleus was derived.
This proved that the nucleus contains the genetic information responsible for controlling cellular traits and heredity.
0 likesView Solution
85
BiologyEasyMCQAIPMT · 1992
Which of the following is an endomembrane system component?
A
Golgi apparatus
B
Endoplasmic reticulum
C
Microfilaments
D
Microtubules
Solution
(A, B) The endomembrane system includes organelles that work together to modify,package,and transport lipids and proteins. These include the endoplasmic reticulum,Golgi apparatus,lysosomes,and vacuoles. Microfilaments and microtubules are part of the cytoskeleton and are not part of the endomembrane system. Since both $A$ and $B$ are components of the endomembrane system,this question typically refers to the system as a whole. However,in many contexts,the endoplasmic reticulum is considered the starting point of this system.
0 likesView Solution
86
BiologyEasyMCQAIPMT · 1992
Ribosomes are considered the center of which process?
A
Respiration
B
Photosynthesis
C
Protein synthesis
D
Fat synthesis
Solution
(C) Ribosomes are small,dense,granular structures composed of $RNA$ and proteins.
They are the sites where amino acids are assembled into polypeptide chains,a process known as protein synthesis.
Therefore,ribosomes are often referred to as the 'protein factories' of the cell.
They are the sites where amino acids are assembled into polypeptide chains,a process known as protein synthesis.
Therefore,ribosomes are often referred to as the 'protein factories' of the cell.
0 likesView Solution
87
BiologyEasyMCQAIPMT · 1992
Which of the following cell organelles lacks a membrane?
A
Nucleolus
B
Lysosome
C
Mitochondria
D
Chloroplast
Solution
(A) The $Nucleolus$ is a non-membrane-bound structure found within the nucleus of eukaryotic cells.
It is primarily involved in the synthesis of ribosomal $RNA$ $(rRNA)$ and the assembly of ribosomes.
In contrast,$Lysosomes$,$Mitochondria$,and $Chloroplasts$ are all membrane-bound organelles.
It is primarily involved in the synthesis of ribosomal $RNA$ $(rRNA)$ and the assembly of ribosomes.
In contrast,$Lysosomes$,$Mitochondria$,and $Chloroplasts$ are all membrane-bound organelles.
0 likesView Solution
88
BiologyMediumMCQAIPMT · 1992
On which structure are the $F_0-F_1$ particles of oxysomes located?
A
Thylakoids
B
Surface of mitochondria
C
Inner mitochondrial membrane
D
Surface of chloroplast
Solution
(C) The $F_0-F_1$ particles,also known as oxysomes or elementary particles,are found on the inner mitochondrial membrane.
These particles are involved in the process of oxidative phosphorylation,where they synthesize $ATP$ using the proton gradient generated across the inner mitochondrial membrane.
The $F_1$ headpiece projects into the mitochondrial matrix,while the $F_0$ base is embedded within the inner membrane.
These particles are involved in the process of oxidative phosphorylation,where they synthesize $ATP$ using the proton gradient generated across the inner mitochondrial membrane.
The $F_1$ headpiece projects into the mitochondrial matrix,while the $F_0$ base is embedded within the inner membrane.
0 likesView Solution
89
BiologyMediumMCQAIPMT · 1992
All plastids have similar structures because they ..........
A
store starch,lipids,and proteins.
B
can be converted from one type to another.
C
perform the same function.
D
are present together.
Solution
(B) Plastids are organelles found in plant cells and euglenoids. They are classified into chloroplasts,chromoplasts,and leucoplasts based on the type of pigments they contain. All these plastids originate from the same precursor organelle called the proplastid. Because they share a common developmental origin and can be converted from one type to another (e.g.,a chloroplast can turn into a chromoplast during fruit ripening),they possess similar structural features,such as a double-membrane envelope and an internal matrix.
0 likesView Solution
90
BiologyEasyMCQAIPMT · 1992
One $\mathring{A} = $ ............... . (in $\mu m$)
A
$0.01$
B
$0.001$
C
$0.0001$
D
$0.00001$
Solution
(C) The $\mathring{A}$ is a unit of length equal to $10^{-10} \, m$.
One micrometer $(\mu m)$ is equal to $10^{-6} \, m$.
To convert $\mathring{A}$ to micrometers:
$1 \, \mathring{A} = 10^{-10} \, m = 10^{-4} \times 10^{-6} \, m = 10^{-4} \, \mu m$.
$10^{-4} \, \mu m = 0.0001 \, \mu m$.
Therefore, $1 \, \mathring{A} = 0.0001 \, \mu m$.
One micrometer $(\mu m)$ is equal to $10^{-6} \, m$.
To convert $\mathring{A}$ to micrometers:
$1 \, \mathring{A} = 10^{-10} \, m = 10^{-4} \times 10^{-6} \, m = 10^{-4} \, \mu m$.
$10^{-4} \, \mu m = 0.0001 \, \mu m$.
Therefore, $1 \, \mathring{A} = 0.0001 \, \mu m$.
0 likesView Solution
91
BiologyMediumMCQAIPMT · 1992
Efferent nerve fibers carry impulses from:
A
Effector organ to $CNS$
B
$CNS$ to muscle
C
$CNS$ to sensory receptor
D
Sensory receptor to $CNS$
Solution
(B) The human neural system is divided into two parts: the Central Neural System $(CNS)$ and the Peripheral Neural System $(PNS)$.
$PNS$ consists of nerve fibers that are classified into two types: afferent nerve fibers and efferent nerve fibers.
Afferent nerve fibers transmit impulses from tissues/organs to the $CNS$.
Efferent nerve fibers transmit regulatory impulses from the $CNS$ to the concerned peripheral tissues/organs (such as muscles or glands).
Therefore,efferent nerve fibers carry impulses from the $CNS$ to the effector organs like muscles.
$PNS$ consists of nerve fibers that are classified into two types: afferent nerve fibers and efferent nerve fibers.
Afferent nerve fibers transmit impulses from tissues/organs to the $CNS$.
Efferent nerve fibers transmit regulatory impulses from the $CNS$ to the concerned peripheral tissues/organs (such as muscles or glands).
Therefore,efferent nerve fibers carry impulses from the $CNS$ to the effector organs like muscles.
0 likesView Solution
92
BiologyEasyMCQAIPMT · 1992
The $Vagus$ nerve is the $...$ cranial nerve.
A
$X$
B
$IX$
C
$VII$
D
$V$
Solution
(A) The $Vagus$ nerve is the $10th$ cranial nerve,denoted as $X$ in Roman numerals. It is the longest cranial nerve and plays a crucial role in the parasympathetic nervous system,regulating heart rate,gastrointestinal peristalsis,and sweating.
0 likesView Solution
93
BiologyEasyMCQAIPMT · 1992
The pupil is a part of the ........
A
Iris
B
Choroid
C
Choroid and Retina
D
Iris and Choroid
Solution
(A) The eye consists of three layers: the outer sclera,the middle choroid,and the inner retina.
The iris is the visible colored portion of the eye,which is a continuation of the choroid.
The pupil is the aperture or opening located in the center of the iris.
Therefore,the pupil is functionally and structurally associated with the iris,which is part of the middle layer (uvea) of the eye.
The iris is the visible colored portion of the eye,which is a continuation of the choroid.
The pupil is the aperture or opening located in the center of the iris.
Therefore,the pupil is functionally and structurally associated with the iris,which is part of the middle layer (uvea) of the eye.
0 likesView Solution
94
BiologyEasyMCQAIPMT · 1992
Ivan Pavlov conducted experiments on ......... .
A
Simple reflex action
B
Conditioned reflex action
C
Threshold reflex action
D
Origin of life
Solution
(B) Ivan Pavlov was a Russian physiologist known primarily for his work in classical conditioning.
He conducted experiments on dogs to demonstrate the concept of $Conditioned \text{ } reflex \text{ } action$.
In his experiments, he paired a neutral stimulus (like a bell) with an unconditioned stimulus (food) to elicit a conditioned response (salivation) in dogs.
He conducted experiments on dogs to demonstrate the concept of $Conditioned \text{ } reflex \text{ } action$.
In his experiments, he paired a neutral stimulus (like a bell) with an unconditioned stimulus (food) to elicit a conditioned response (salivation) in dogs.
0 likesView Solution
95
BiologyMediumMCQAIPMT · 1992
The blastopore is the ....................
A
opening of the neural tube
B
opening of the archenteron
C
future anterior end of the embryo
D
opening found in the blastocoel
Solution
(B) The blastopore is the opening that connects the archenteron (primitive gut) to the outside of the embryo during the gastrulation stage of embryonic development.
In protostomes,the blastopore develops into the mouth,while in deuterostomes,it develops into the anus.
In protostomes,the blastopore develops into the mouth,while in deuterostomes,it develops into the anus.
0 likesView Solution
96
BiologyMediumMCQAIPMT · 1992
Which substance is most abundant in a cell?
A
Water
B
Proteins
C
Nucleic acids
D
Lipids
Solution
(A) In a typical living cell, water is the most abundant chemical substance, accounting for approximately $70-90\%$ of the total cellular mass. Among the organic compounds, proteins are generally the most abundant, but when considering all molecules including inorganic ones, water is the primary component.
0 likesView Solution
97
BiologyEasyMCQAIPMT · 1992
Living cells contain $60-75\%$ water. How much water is present in the human body?
A
$60-65\%$
B
$50-55\%$
C
$75-80\%$
D
$65-70\%$
Solution
(D) Water is the most abundant chemical compound in living organisms.
In a typical human body,water constitutes approximately $65-70\%$ of the total body weight.
This water is essential for various physiological processes,including acting as a solvent for biochemical reactions,thermoregulation,and transport of nutrients and waste products.
Therefore,the correct range for the water content in the human body is $65-70\%$.
In a typical human body,water constitutes approximately $65-70\%$ of the total body weight.
This water is essential for various physiological processes,including acting as a solvent for biochemical reactions,thermoregulation,and transport of nutrients and waste products.
Therefore,the correct range for the water content in the human body is $65-70\%$.
0 likesView Solution
98
BiologyEasyMCQAIPMT · 1992
Glycogen is a polymer of ......... .
A
Galactose
B
Glucose
C
Fructose
D
Sucrose
Solution
(B) Glycogen is a polysaccharide that serves as the primary form of energy storage in animals and fungi.
It is a branched polymer composed of repeating units of $D-glucose$ linked by $\alpha-1,4-glycosidic$ bonds in the linear chains and $\alpha-1,6-glycosidic$ bonds at the branching points.
Therefore,the correct answer is $Glucose$.
It is a branched polymer composed of repeating units of $D-glucose$ linked by $\alpha-1,4-glycosidic$ bonds in the linear chains and $\alpha-1,6-glycosidic$ bonds at the branching points.
Therefore,the correct answer is $Glucose$.
0 likesView Solution
99
BiologyMediumMCQAIPMT · 1992
From which of the following are amino acids synthesized?
A
Proteins
B
Fatty acids
C
Essential oils
D
$\alpha$-keto acids
Solution
(D) Amino acids are the building blocks of proteins. In biological systems,they are primarily synthesized from $\alpha$-keto acids through the process of transamination. In this process,an amino group $(-NH_2)$ is transferred from an existing amino acid to an $\alpha$-keto acid,converting it into a new amino acid. For example,pyruvic acid (an $\alpha$-keto acid) is converted into alanine.
0 likesView Solution
100
BiologyMediumMCQAIPMT · 1992
Adenine is a .............. .
A
Purine
B
Pyrimidine
C
Nucleoside
D
Nucleotide
Solution
(A) Adenine is a nitrogenous base found in $DNA$ and $RNA$.
Nitrogenous bases are classified into two categories: Purines and Pyrimidines.
Purines include Adenine $(A)$ and Guanine $(G)$,which are double-ring structures.
Pyrimidines include Cytosine $(C)$,Thymine $(T)$,and Uracil $(U)$,which are single-ring structures.
Therefore,Adenine is a Purine.
Nitrogenous bases are classified into two categories: Purines and Pyrimidines.
Purines include Adenine $(A)$ and Guanine $(G)$,which are double-ring structures.
Pyrimidines include Cytosine $(C)$,Thymine $(T)$,and Uracil $(U)$,which are single-ring structures.
Therefore,Adenine is a Purine.
0 likesView Solution
Vedclass Products
For Students
Vedclass Test Series
Mock tests in real AIPMT style covering Biology with performance analysis. 5-day free trial.
Start Free TrialFor Teachers
Exam Paper Generator
Generate Set A/B/C/D Biology papers from 7.5L+ questions in 2 minutes. 3 chapters free.
Try FreeFor Institutes
Online Exam Module
Run live AIPMT mock exams with unlimited students, 360° analytics & white-label branding.
See DemoFrequently Asked Questions
How many Biology questions are in AIPMT 1992?
There are 177 Biology questions from the AIPMT 1992 paper on Vedclass, each with a detailed step-by-step solution in English.
Are AIPMT 1992 Biology solutions available in English?
Yes. All solutions on this page are in English. You can also switch to English or Hindi using the language buttons above the questions.
Can I practice AIPMT 1992 Biology as a timed test?
Yes. Use the Vedclass Test Series to attempt a full AIPMT mock test covering Biology with time limits and instant score analysis.
Can teachers create Biology papers from AIPMT previous year questions?
Yes. The Vedclass Exam Paper Generator lets teachers mix AIPMT Biology questions and generate Set A/B/C/D papers in minutes.
For Teachers & Institutes
Build a Custom Biology Paper
Pick AIPMT 1992 Biology questions, set difficulty, and generate Set A/B/C/D in 2 minutes.