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The correct answer is Methane.

Key Points

• Biogas is produced under anaerobic conditions; the process is denominated as anaerobic digestion.
• It converts the harmful methane gas into less harmful carbon dioxide gas.
• Biogas is usually made up of:
• Around 50-70% methane (CH4).
• Around 25-45% carbon dioxide (CO2).
• These gases form biogas and can be used as a source of energy as it is inflammable.
• Biogas produced by microbes is used as a source of energy in rural areas.
• Biogas can be compressed after the removal of Carbon dioxide and can be used to power motor vehicles.Animal and plant wastes can also be used to produce biogas.

The correct answer is Strontium.

Key Points

• The volatile metal compounds of copper, calcium, and strontium are generally used in fireworks to get colours.
• This is because these metals have low ionisation enthalpies.
• Strontium Carbonate imparts red colour, Calcium Chloride imparts orange colour, and Copper Chloride imparts blue colour.
• A firecracker contains a fuel charcoal, sulfur and potassium nitrate -similar to gunpowder.
• When the firework explodes, the metal particles start oxidizing and heat is produced.
• This heat excites the metal particles and colourful light depending on the metal is emitted.
• Enthalpy is the total sum of the internal energy and the product of the pressure and volume of a thermodynamic system.
• Ionization energy is the energy that is required to remove an electron from its orbit to a point where it is no longer associated with that atom

The correct answer is Halophytes.

Key Points Salt-loving plants -

• They are called Halophytes.
• They survive in saline environments and can tolerate salt concentrations of up to 1M NaCl.
• They constitute about 1% of the total flora of the world.
• Example: **Mangroves.**​

Additional InformationShade-loving plants:

• They are called Sciophytes.
• They thrive better in low intensity sunlight.
• They are usually found growing as undergrowth of tall plants in a forest.
• Example: Black pepper.

Water-loving plants:

• They are called Hydrophytes.
• They survive either partially or completely submerged in water.
• They may also include plants growing in water-logged soil.
• Example: Water lily, duckweed.

Sun-Loving Plants:

• The sun-loving plants are known as heliophytes or sunstroke plants.
• They are adapted to thrive in direct sunlight.
• They are common in open fields and meadows.
• Some features of heliophytes:
• Thicker stems with well-developed xylem.
• Shorter internodes with branching.
• Thicker leaf blades with smaller stomata.
• Leaves with thick cuticle and numerous hairs.
• Leaf orientation is not at right angles.
• Examples: Banyan, Thyme.

​Xerophyte:

• A xerophyte is a species of plant that has adaptations to survive in an environment with little liquid water, such as a desert or an ice- or snow-covered region in the Alps or the Arctic.

Glycophytes:

• Glycophytes are salt-sensitive plants that do not grow in soil or water of high salinity.
• Salt-sensitive plants such as glycophytes do not have the ability to grow and complete their life cycle in salt stress conditions.

​Mesophyte:

• Mesophytes are terrestrial plants which are neither adapted to particularly dry nor particularly wet environments.
• An example of a mesophytic habitat would be a rural temperate meadow, which might contain goldenrod, clover, oxeye daisy, and Rosa multiflora

The correct answer is chlorophyll.

Key Points

• Fungi are plants that lack chlorophyll and also they are distinguished by their unique structure as well as physiological features.
• Fungi also have a cell wall that is made up of chitin and get the nutrients through absorption. As there is a lack of chlorophyll in fungi so photosynthesis will not take place.

The correct answer is Pollination is best defined as the transfer of pollen grain from anther to stigma.

Key Points

• Pollination: The process of transfer of pollen (from male reproductive part i.e. anther) to the stigma (from female reproductive part i.e. carpel) of flowering plants is called Pollination.
• Fertilization: It is the fusion of male and female gamete.

The correct answer is soil.

Key Points

• The plants mainly receive their nutrients from the soil.
• Soil is the main source of nutrients for plants.

Additional Information

• The pH is an important factor that influences the availability of essential nutrients to the plants.
• The soil of slightly acidic that is of 6 and slightly alkaline that is of 7.5 is satisfactory for the growth of most crops.
• Plant roots can only absorb nutrients after they have been transformed into certain ionic forms.
• Potassium helps the roots to penetrate deep into the soil to absorb nutrients quickly.
• ​Phosphate, potassium, and zinc are the main nutrient ions moving as a result of diffusion.

The correct option is Gymnosperm.

Key Points

• The gymnosperms are a group of seed-producing plants that includes cycads, Ginkgo, gnetophytes, and conifers.
• The gymnosperms are also known as Acrogymnospermae.
• Over 150 species of timber are produced in India.
• The largest group of living gymnosperms are the conifers (pines, cypresses, and relatives).
• After that Cycads, gnetophytes, and Ginkgo biloba (a single living species).

Additional InformationAngiosperm

• In these plants, a seed is produced by flowering plants and is enclosed within an ovary.
• The lifecycle of these plants is cyclical.
• They are generally hardwood type.
• The reproductive system is present in flowers in these plants.

Monocotyledons:

• Monocotyledons commonly referred to as monocots, are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon.

​Dicotyledons:

• The dicotyledons, also known as dicots.
• It this group all the flowering plants were formerly divided.
• The name refers to one of the typical characteristics of the group: namely, that the seed has two embryonic leaves or cotyledons.

Option 3 is the correct answer. Chloroquine is a medication primarily used to prevent and treat malaria in areas where malaria remains sensitive to its effects.

Scurvy is a disease resulting from a lack of vitamin C (ascorbic acid). And Thiamine or thiamin also called vitamin B1, is one the of B vitamins.

The correct answer is earthworm.

Key Points

• An earthworm is a terrestrial invertebrate that belongs to the order Opisthopora.
• They exhibit a tube-within-a-tube body plan, are externally segmented with corresponding internal segmentation, and usually have setae on all segments.
• While humans and many other species have red blood, due to the iron in their hemoglobin, other animals have different colored blood.
• Spiders (as well as horseshoe crabs and certain other arthropods) have blue blood due to the presence of copper-based hemocyanin in their blood.
• Some animals, such as the sea cucumbers, even have yellow blood.
• The yellow coloration is due to a high concentration of the yellow vanadium-based pigment, vanabin.
• Unlike hemoglobin and hemocyanin, vanabin does not seem to be involved in oxygen transport.

The correct answer is glucose.

Key Points

• Dietary carbohydrates are digested to glucose, fructose and/or galactose, and absorbed into the blood in the small intestine.

Carbohydrates: 

• General formula: C_nH_2nO_n
• The simplest form of carbohydrate is Glucose.
• Carbohydrates provide instant energy.
• Honey has the maximum quantity of carbohydrates.
• Sources of carbohydrates are banana, potato, rice, wheat, etc

Types of Carbohydrates:

1. Monosaccharide(C₆H₁₂O₆):

• Glucose:
• ​The simplest form of carbohydrate.
• Fructose:
• Present in fruits.
• Sweetest form of carbohydrates.
• Galactose:
• Present in milk.

2. Disaccharide (C₁₂H₂₂O₁₁):

• Maltose: Glucose + Glucose
• Sucrose: Glucose + Fructose
• Present in sugarcane.
• Lactose: Glucose + Galactose
• Present in the Mother's milk.

3. Polysaccharide:

• Cellulose:
• Present in plants.
• Degraded by cellulase enzyme.
• Starch: 
• Present in plants.
• Plants stores their food in the form of starch.
• Degraded by Ptyalin enzyme.
• Glycogen:
• Present in animals.
• Degraded by Amylase enzyme.