Female Reproductive System
The female germ-cells or eggs are produced in the ovaries.
The egg is transported from the ovary to the womb through a thin oviduct known as fallopian tube.
The two oviducts unite and form an elastic bag-like structure known as the uterus, which opens into the vagina through the cervix.
During the sexual intercourse, most likely, the egg and the sperm (zygote) get fertilized and implanted in the lining of the uterus.
The thickened lining (of the uterus) and richly supplied blood nourish the growing embryo (in the uterus).
The embryo receives nutrition from the mother’s blood with the help of a special tissue known as placenta.
Likewise, the development of a child inside the mother’s body, takes about nine months.
1 Like
Sexual Reproduction in Flowering Plants
Flowers have different parts, such as sepals, petals, stamens, and carpels. Among these, stamens and carpels are the reproductive parts and contain the germ-cells.
Stamen is the male reproductive part, which produces pollen grains (yellowish substance).
Carpel, which is present in the center of a flower, is the female reproductive part.
Carpel is made of three parts.
The bottom part, which is swollen, is the ovary; the middle part, which is elongated, is known as the style; and the terminal part, which may be sticky, is known as the stigma.
The ovary contains ovules and each ovule has an egg cell.
The male germ-cell that produced by the pollen grain fuses with the female gamete present in the ovule.
The fusion of the germ-cells or fertilization produces zygote, which is capable of growing into a new plant.
The flower, which contains either stamens or carpels, is known as unisexual, such as papaya, watermelon, etc.
The flower, which contains both stamens and carpels, is known as bisexual, such as Hibiscus, mustard, etc.
1 Like
Sexual Reproduction
The sexual mode of reproduction comprises the process of combining DNA from two different individuals.
There are two germ-cells (responsible for producing a new organism); one is large and contains the food-stores whereas the other one is smaller and likely to be motile.
The motile germ-cell, normally, is known as the ‘male gamete’ and the germ-cell containing the stored food is known as the ‘female gamete.’
1 Like
Some important extra edge points that you should know before attempting NEET exam
Length of small bowel ‣ 6.25 m
⊚ Weight of liver (male) ‣ 1.4-1.8 kg.
⊚ Liver weight (in female) ‣ 1.2-1.4 kg
⊚ Largest gland ‣ Liver
⊚ Most regenerative capacity ‣ in the liver
⊚ Least regenerative capacity ‣ in the brain
⊚ Hardest part of the body ‣ Tooth enamel
⊚ Largest salivary gland ‣ Parotid gland
⊚ Normal body temperature ‣ 98.4 °F(37°C)
⊚ Amount of blood in the body ‣ 5.5 liters
⊚ Average amount of hemoglobin (men) ‣ 13-16 g/dl
⊚ Average amount of hemoglobin (in women) ‣ 11.5-14 g/dl
⊚ Total number of WBCs ‣ 5000-10000/cu mm.
⊚ Smallest WBC ‣ Lymphocyte
⊚ Largest WBC ‣ Monacid
⊚ Life span of RBC ‣ 120 days
⊚ Life span of WBC ‣ 2-5 days
⊚ Blood clotting time ‣ 3-6 minutes
⊚ omnibus blood group ‣ AB
⊚ Universal donor blood group ‣ O
⊚ normal blood pressure ‣ 120/80 Hg
⊚ Normal pulse rate at birth ‣ 140 times-minute
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
Normal pulse rate at 1 year old ‣ 120 bpm
⊚ Normal pulse rate at age 10 ‣ 90 times-minute
⊚ Normal pulse rate adult ‣ 70 times-minute
⊚ Heart rate ‣ 72 beats-minute
⊚ Largest vein ‣ inferior vena cava
⊚ Largest artery ‣ Abdominal aorta
⊚ Weight of kidney ‣ 150 grams
⊚ Head weight ‣ 1220-1400 grams
⊚ Length of spinal cord ‣ 42-45 cm
⊚ Number of cranial nerves ‣ 12 pairs
⊚ Number of spinal nerves ‣ 31 pairs
⊚ longest nerve ‣ sciatic
⊚ Thinnest and smallest nerve ‣ Trochlear
⊚ Largest nerve ‣ Trigeminal
⊚ Largest cell ‣ nerve cell
⊚ Largest endocrine gland ‣ Thyroid
⊚ incidental gland ‣ adrenal
⊚ Smallest endocrine gland ‣ Pituitary gland
⊚ Gestation period ‣ 266-270 days
⊚ Total number of bones ‣ 206
⊚ Smallest bone ‣ stapes (in the middle ear)
⊚ Longest bone ‣ Femur (in thigh)
⊚ Total number of kasarukas ‣ 33
⊚ Total number of muscles ‣ 639
⊚ Longest muscle ‣ Sartorius
#neet-ug #neet-ug:neet-2024 #neet-ug:biology
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
Extra edge of ncert
☆1☆ Triple helical model of collagen was given by G.N. Ramachandran
★2★ Ramachandran was influenced by Linus Pauling
★3★ Darwin was influenced by Malthus
★4★ P. Maheshwari was influenced by Dr. W. Dudegon
★5★ a- helix & b- sheet structures was published by Linus Pauling
★6★ Anton von Leeuwenhoek first saw & described a live cell.
★7★ Cell theory was given by Schleiden & Schwann.
★8★ Cell theory was modified by Rodolf Virchow (1855)
★9★ Fluid mosaic model was given by Singer & Nicholson(1972)
★10★ G.B. discovered by Camillo golgi(1988)
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
𝘓𝘐𝘝𝘌𝘙 ( 𝘏𝘦𝘱𝘢𝘳 )
#digestion_and_absorption
#Keypoints
• It is largest exocrine gland of the body, weighting about 1.5kg in an average adult.
• Position – Upper right side just below the diaphragm.
• It is high regeneration power.
• Covering of unit of liver (lobule) and liver (Glisson’s capsule)
• Phagocytic cells in liver = kupffer cell.
• It is divided into two principal lobes separated by falciform ligament.
(i) Right lobe (large)
(ii) Left lobe (Small)
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
𝘛𝘠𝘗𝘌𝘚 𝘖𝘍 𝘛𝘌𝘌𝘛𝘏 𝘐𝘕 𝘏𝘜𝘔𝘈𝘕
• 4 types of Teeth +nt in human.
(1) Thecodont – teeth +nt in socket
(2) Bunodont – small cusp +nt
(3) Diphyodont – two set of teeth
(i) Pri. Dentition / milk teeth /
deciduous teeth /
temporary teeth [ 20 teeth ]
(ii) Sec. Dentition /
adult teeth /
permanent teeth
[ 32 teeth ]
(4) Heterodont
(i) Incisor ( I ) – Cutting
(ii) Canine ( C ) – Tearing
(iii) Premolar ( Pm ) –
Grinding
(iv) Molar ( M ) – Grinding
★ 𝐃𝐞𝐧𝐭𝐚𝐥 𝐅𝐨𝐫𝐦𝐮𝐥𝐚 
– Arrangment of teeth in each half of the upper and lower jaw in the order I, C, Pm, M is represented by a dental formula.
D.F = no. of teeth in upper half jaw / no. of teeth in lower half jaw
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
VIVIPAROUS
★Development of zygote takes place inside the body of organisms and produces young ones.
Ex- Human, dog, horse etc
★In flowering plants, zygote is formed inside the ovule.
■ After fertilisation, sepals, petals and stamens of flower fall off.
■ The zygote develops into embryo and ovules into seeds.
■ The ovary develops into fruits which develop a thick wall called pericarp protective in function.
■After dispersal, seeds germinate under favorable condition to produce new plants.
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
MORPHOLOGY OF FLOWERING PLANTS 
PHYLLOTAXY
■The pattern of arrangement of leaves on the stem or branch is called phyllotaxy. It helps to avoid overcrowding and provide every leaf with optimum sunshine.
★Phyllotaxy is usually of three types:-
[1]ALTERNATE PHYLLOTAXY
A single leaf arises at each node in alternate manner,
Examples:diamonds:
■China rose
■mustard
■sunflower
[2]OPPOSITE PHYLLOTAXY
A pair of leaves axises at each node and opposite to each other,
Examples:diamonds:
■Calotropis
■ Guava
[3]WHORLED PHYLLOTAXY
If more than two leaves arise at a node and form a whorl, it is called whorled. The leaves of one whorl generally alternate with those of the adjacent whorls in order to provide maximum exposure,
Examples:diamonds:
■Nerium (kaner)
■Alstonia.
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
ALL IMPORTANT EXAMPLES OF PLANT KINGDOM
CHLOROPHYCEAE:green_heart:
■ Chlorella ■ Spirogyra,
■ Volvox ■ Ulothrix
■chara ■ Chlamydomonas,
■Cladophora
PHAEOPHYCEAE
■ Ectocarpus ■kelp,
■Fucus ■ Laminaria
■ Dictyota ■Sasagassum.
RHODOPHYCEAE
■ Gracilaria ■Gelidium ■Porphyra, ■Polysiphonia
BRYOPHYTES
☆LIVERWORTS 
■ Marchantia
☆Mosses💙
■ Funaria ■Sphagnum
PTERIDOPHYTES
★HOMOSPOROUS
■ Fern ■ Equisetum
★ HETEROSPOROUS
■ Salvinia ■Selaginella ■Lycopodium ■Pteris, ■Dryopteris ■ Adiantum, ■Psilotum.
GYMNOSPERMS
■ Cycas ■pinus
■Ginkgo ■Sequoia ■Cedrus
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
𖤐★︎:butterfly: 𝙴𝙽𝚉𝚈𝙼𝙴𝚂 
★︎𖤐
★︎ ᴇɴᴢʏᴍᴇs ᴀʀᴇ ᴘʀᴏᴛᴇɪɴs ᴡʜɪᴄʜ ᴄᴀᴛᴀʟʏsᴇ ʙɪᴏᴄʜᴇᴍɪᴄᴀʟ ʀᴇᴀᴄᴛɪᴏɴs ɪɴ ᴛʜᴇ ᴄᴇʟʟs
★︎ ᴛʜᴇʏ ᴀʀᴇ ᴅᴇɴᴀᴛᴜʀᴇᴅ ᴀᴛ Hɪɢʜ ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇs.
★︎ ᴇɴᴢʏᴍᴇs ɢᴇɴᴇʀᴀʟʟʏ ғᴜɴᴄᴛɪᴏɴ ɪɴ ᴀ ɴᴀʀʀᴏᴡ ʀᴀɴɢᴇ ᴏғ ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇ ᴀɴᴅ ᴘH. Eᴀᴄʜ ᴇɴᴢʏᴍᴇ sʜᴏᴡs ɪᴛs ʜɪɢʜᴇsᴛ ᴀᴄᴛɪᴠɪᴛʏ ᴀᴛ ᴘᴀʀᴛɪᴄᴜʟᴀʀ ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇ ᴀɴᴅ ᴘH ᴄᴀʟʟᴇᴅ ᴛʜᴇ ᴏᴘᴛɪᴍᴜᴍ ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇ ᴀɴᴅ ᴏᴘᴛɪᴍᴜᴍ ᴘH.
★︎ ᴡɪᴛʜ ɪɴᴄʀᴇᴀsᴇ ɪɴ sᴜʙsᴛʀᴀᴛᴇ ᴄᴏɴᴄᴇɴᴛʀᴀᴛɪᴏɴ , ᴛʜᴇ ᴠᴇʟᴏᴄɪᴛʏ ᴏғ ᴛʜᴇ ᴇɴᴢʏᴍᴀᴛɪᴄ ʀᴇᴀᴄᴛɪᴏɴ ʀɪsᴇ ᴀᴛ ғɪʀsᴛ . Tʜᴇ ʀᴇᴀᴄᴛɪᴏɴ ᴜʟᴛɪᴍᴀᴛᴇʟʏ ʀᴇᴀᴄʜᴇs ᴀ ᴍᴀxɪᴍᴜᴍ ᴠᴇʟᴏᴄɪᴛʏ ( Vᴍᴀx) ᴡʜɪᴄʜ ɪs ɴᴏᴛ ᴇxᴄᴇᴇᴅᴇᴅ ʙʏ ᴀɴʏ ғᴜʀᴛʜᴇʀ ʀɪsᴇ ɪɴ ᴛʜᴇ ᴄᴏɴᴄᴇɴᴛʀᴀᴛɪᴏɴ ᴏғ ᴛʜᴇ sᴜʙsᴛʀᴀᴛᴇ .
★︎ ᴛʜᴇ ᴀᴄᴛɪᴠɪᴛʏ ᴏғ ᴀɴ ᴇɴᴢʏᴍᴇ ɪs ᴀʟsᴏ sᴇɴsɪᴛɪᴠᴇ ᴛᴏ ᴛʜᴇ ᴘʀᴇsᴇɴᴄᴇ ᴏғ sᴘᴇᴄɪғɪᴄ ᴄʜᴇᴍɪᴄᴀʟs ᴛʜᴀᴛ ʙɪɴᴅ ᴛᴏ ᴛʜᴇ ᴇɴᴢʏᴍᴇ.
★︎ ᴇɴᴢʏᴍᴇs ᴀʀᴇ sᴜʙsᴛʀᴀᴛᴇ sᴘᴇᴄɪғɪᴄ ɪɴ ᴛʜᴇɪʀ ᴀᴄᴛɪᴏɴ.
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
VIRUSES
➢ not considered truly ‘living’
➢ inert outside their specific host cell
➢ take over the machinery of the host cell to replicate, killing the host
➢ In addition to proteins, viruses also contain genetic material- RNA or DNA
➢ viruses that infect plants have single stranded RNA
➢ that infect animals could be either single or double stranded RNA or double stranded DNA
➢ bacteriophages are generally dsDNA viruses
➢ The protein coat called capsid made of small subunits called capsomeres.
☆ These capsomeres are arranged in helical or polyhedral geometric forms.
➢ Diseases in animals- mumps, small pox, herpes and influenza.
➢ Symptoms in plants- mosaic formation, leaf rolling and curling, yellowing and vein
clearing, dwarfing and stunted growth
🟩 VIROIDS 🟩
➢ Smaller than viruses
➢ Low molecular weight RNA and no protein coat
➢ Potato spindle tuber disease is caused by potato spindle tuber viroid
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
IMPORTANT POINTS OF NCERT OF REPRODUCTION IN ORGANISMS
PARTHENOGENESIS💛 Development of an egg into an embryo without fertilisation.
E.g. Rotifers, honeybees, turkey and some lizards.
●Meiocytes are specialised cells of diploid organisms which undergo meiosis to produce gametes.
MONOECIOUS PLANTS:purple_heart:: Plants having both male and females flowers on same individual. E.g. Cucurbits and coconut.
DIOECIOUS PLANTS:blue_heart:: Plants having male and female flowers on separate individuals. E.g. Papaya and date palm.
●Bamboo species flower only once in their life time generally after 50-100 yr.
●Strobilanthus kunthiana: Flowers once in 12 years. (Kerarala, Karnataka and Tamil Nadu)
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
EVOLUTION IMPORTANT NCERT POINTS
EXAMPLES OF ANALOGOUS ORGAN
■WINGS OF BAT AND BIRDS ARE ANALOGOUS TO WINGS OF INSECTS
■STING OF BEE AND SCORPION
■PHYLLOCLADE OF RUSCUS AND LEAF
■CHLORAGOGANE CELL OF PHERETIMA AND LIVER OF VERTEBRAE
■POTATO AND SWEET POTATO
■EYES OF OCTOPUS AND MAMMALS (DIFFERENT IN THEIR RETINAL POSITION)
■FLIPPERS OF PENGUIN (BIRD) AND DOLPHINS (MAMMALS)
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
ENZYMES LOCK AND KEY HYPOTHESIS
This hypothesis was given by Emil Fischer (1894). According to this hypothesis, both enzyme and substrate molecules have specific geometrical shapes. It is similar to the system of lock and key, which have, special geometrical shapes in the region of their activity. Just as a lock can be opened by its specific key, a substrate molecule can be acted upon by a particular enzyme.
This also explains the specificity of enzyme action. After coming in contact with the active site of the enzyme, the substrate molecules or reactants form a complex called enzyme substrate complex. In the enzyme substrate complex, the molecules of the substrate undergo chemical change and form products.
This theory explains how a small concentration of enzyme can act upon a large amount of the substrate. It also explains how the enzyme remains unaffected at the end of chemical reaction.
Enzyme + Substrate → Enzyme - Substrate Complex Enzyme - Substrate → Complex Enzyme + End Products
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
ENZYMES INDUCED FIT HYPOTHESIS
This hypothesis was proposed by Koshland (1960). According to this hypothesis the active site of the enzyme does not initially exist in a shape that is complementary to the substrate but is induced to assume the complementary shape as the substrate becomes bound to the enzyme. There are two ends
(a) Buttressing group is meant for supporting the substrate
(b) Catalytic group is meant for catalysing the reaction. When substrate comes in contact with the buttressing group, the active site changes to bring catalytic group opposite to the substrate
1 Like
BIOLOGICAL CLASSIFICATION
COMMON NAMES OF FUNGI
1)Myxomycetes - Slime fungi
2)Eumycetes - True fungi
3)Phycomycetes - Algal fungi
4)Ascomycetes - Sac fungi
5)Allomyces - Water molds
6)Basidiomycetes - Club fungi
7)Mucor - Bread mold
8)Penicillum - Green/blue mold
9)Pezzia - Cup fungi
10)Polyporus - Pore fungi
11)Puccinia - Rust fungus
12)Ustilago - Smut fungus
13)Aspergillus - Conidial fungus
14)Yeast - Sugar fungi
15)Claviceps - Ergot fungi
16)Auricularia - Jelly fungi
17)Fomes - Shelf fungi
18)Clavicornona - Coral fungi
19)Rhizopus - Conjugation fungi
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
PLANT KINGDOM KEY POINTS
Mosses
Two stages
- protonema (develop directly from spore)
- leafy (develop from sec. Protonema as lateral bud)
Pteridophytes
Includes horsetail & ferns.
Used for medicinal purpose. First teresstial plants to posses vascular tissues
Main plant body is sporophyte
Homosporous + heterosporous
GYMNOSPERM
• tap roots
• naked seeds
• thick cuticle & sunken stomats also reduce water loss
• unlike pteridophytes, these have not an independent free living existence.
ANGIOSPERM
• specialised structure called flowers
• divided into monocotyledons + dicotyledons
• double fertilization
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
1 Like
ALGAE IMPORTANT NCERT POINTS
ALGAE
■ chlorophyll-bearing, simple, thalloid, autotrophic and largely aquatic
■habitats: moist stones, soils and wood
■occur in association with
• fungi – lichen
• animals – sloth bear
︎ form and size- highly variable
︎Vegetative reproduction - fragmentation.
︎Asexual reproduction - different types of spores, common – zoospores
︎ Sexual reproduction - fusion of two gametes.
︎ half of the total carbon dioxide fixation on earth is carried by algae
︎increase the level of dissolved oxygen in their immediate environment
︎ paramount importance as primary producers of energy-rich compounds
FORM AND SIZE
★ unicellular - Chlamydomonas
★ colonial form – Volvox
★ filamentous - Ulothrix and Spirogyra.
★ massive plant bodies – kelps
TYPE OF GAMETE
● isogamous flagellated and similar in size
●non-flagellated and similar in size – Spirogyra
■ anisogamous
gametes dissimilar in size
■ oogamous – Volvox, Fucus
USEFUL TO MANKIND
● Porphyra, Laminaria and Sargassum and 70 species of marine algae are used as food.
● algin (brown algae) and carrageen (red algae) produce large amounts of hydrocolloids
●Gelidium and Gracilaria are used to grow microbes and in preparations of ice-creams and jellies
● Chlorella rich in proteins is used as food supplement even by space travellers
Free guidence and doubts - ask.exprto.com
telegram channel. Telegram: Contact @exprto_JEE_NEET_mentorship
Facebook channel. Facebook
Instagram. https://instagram.com/exprto.official?igshid=YmMyMTA2M2Y=
YouTube. Exprto JEE | NEET Mentorship - YouTube
2 Likes