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The correct answer is Chlorophyceae.

Key Points

• Chlorophyceae:-
• The members of Chlorophyceae are commonly called green algae. (Hence option 4 is correct)
• There are about 7000 species in this class.
• The characteristics and features of Chlorophyceae are discussed below:
• They are usually green due to the presence of chlorophyll a, chlorophyll b, carotene, and xanthophyll.
• Their reserve food material is starch.
• The member of Chlorophyceae family exhibits a diverse range of thallus organisation.
• The majority of the members are filamentous.
• They have apical flagella that range in size from two to eight.
• The members of Chlorophyceae reproduce vegetatively, asexually, and sexually by various methods.
• Examples are Chlamydomonas, Chlorella, Volvox, etc.

Additional Information

• Rhodophyceae:
• Rhodophyceae is a red algae with chlorophyll a and chlorophyll d.
• Their reserve food material is Floridian starch.
• They do not have motile stage i.e. they don't have flagella.
• Examples are Porphyra, Polusiphonia, etc.
• Phaeophyceae:-
• Phaeophyceae is a brown algae with chlorophyll a and chlorophyll c.
• The members of Phaeophyceae contain fucoxanthin pigment.
• Their reserve food material is laminarin.
• They have lateral flagella that are unequal in number (about two).
• Examples are Laminaria, Fucus, etc.
• Desmids:-
• These are a group of microscopic green algae that are known for their beautiful and intricate shapes.
• They are found in freshwater habitats all over the world, and there are over 10,000 known species.
• Desmids are single-celled organisms, but some species can form filaments or colonies.

The correct answer is Energy. 

• A kilowatt-hour (kWh) is a unit of energy. It represents the amount of energy consumed or produced when a device with a power rating of one kilowatt (1,000 watts) operates continuously for one hour. In SI units, one kilowatt-hour equals 3.6 million joules (3.6 megajoules) of energy.

Concept:

Power: The rate of work done by the electric energy is called power. It is denoted by P.

• The SI unit of power is the watt (W).
• Watt is a small unit that's why a kilowatt-hour is used as the unit for electrical energy.

1 unit of electric energy: When a one-kilowatt load works for 1 hour then the energy consumed is called 1 unit of electricity.

• 1 Unit of electricity = 1 kWh = 1000 Watt-hour = 3.6 × 106 J
• 1 Kilo-watt = 1000 Watt

1 Watt: The energy consumption rate of 1 joule per second is called 1 watt.

• The capacity to do work or power consumed in a given time is called energy.
• Power is the rate of doing work or the rate at which energy is spent.
• Kilowatt-hour is the unit of energy.

Key Points

• One thousand-watt makes one kilowatt.
• 1 kw hour is equal to 3600 kilojoules.
• For billing units of energy delivered to consumers by electric appliances, this unit is used.
• It is a non-SI metric unit system.
• The one kilowatt of hour sustained for one hour is the composite unit of energy.
• In kilowatt-hours, the electrical energy is typically sold to consumers.
• In terawatt hours, the major energy production or consumption is expressed.
• How much energy is used by us is measured by Kilowatt-hour.

Mistake Points

Energy is the total amount of work done, and power is how fast you can do it. In other words, power is energy per unit of time. Power is watts. Energy is watt-hours.

The correct answer is Cytokinins.

Key Points

• Hormones are regulatory substances produced in an organism.
• Different plant hormones help to coordinate growth, development, and responses to the environment.
• Auxin hormone -  It synthesizes at the shoot tip of the plant and helps the cells to grow longer.
• Gibberellins hormone - It helps in the growth of the stem
• Cytokinin hormone - It promotes cell division.
• Auxin, Gibberellins, and Cytokinins Are examples of Plant growth hormones
• Abscisic acid - It is a type of hormone which signals to stop the growth

The Correct answer is Option 4

Key Points

• Dengue is caused by the Dengue virus, which is transmitted by the bite of infected Aedes mosquitoes.
• It is a viral disease, not a bacterial one.
• Diphtheria, Plague, and Pneumonia can be caused by bacteria:
• Diphtheria: Caused by the bacterium Corynebacterium diphtheriae.
• Plague: Caused by the bacterium Yersinia pestis.
• Pneumonia: Can be caused by various bacteria, including Streptococcus pneumoniae.

The correct answer is Pyruvate

Explanation:

• During intense physical activity, such as rigorous exercise, the oxygen supply to muscle cells may not be sufficient to meet the energy demands of the body.
• This leads to anaerobic respiration in muscle cells, where glucose is partially broken down to generate energy in the form of ATP.
• In the absence of sufficient oxygen, pyruvate (a product of glycolysis) is converted into lactic acid by the enzyme lactate dehydrogenase.
• The accumulation of lactic acid in muscle cells is responsible for muscle cramps and fatigue during prolonged or intense exercise.

Pyruvate is a key intermediate in cellular respiration.

• In the presence of oxygen (aerobic conditions), pyruvate enters the mitochondria and is converted into acetyl-CoA for the citric acid cycle.
• However, under anaerobic conditions, pyruvate is converted into lactic acid in muscle cells to regenerate NAD⁺, which is essential for glycolysis to continue and produce ATP. This process is called lactic acid fermentation.

Other Options:

• ATP: ATP (adenosine triphosphate) is the energy currency of the cell. It is produced during glycolysis, the citric acid cycle, and oxidative phosphorylation. ATP is not directly converted into lactic acid; rather, its production is facilitated by glycolysis, where pyruvate is formed as an intermediate.
• Ethanol: Ethanol is a byproduct of fermentation in certain microorganisms, such as yeast. It is not produced in human muscle cells. Humans undergo lactic acid fermentation, not alcoholic fermentation, under anaerobic conditions.
• Glucose: Glucose is the primary source of energy in cellular respiration. It undergoes glycolysis to produce pyruvate, which can subsequently be converted into lactic acid under anaerobic conditions.

The correct answer is Ovary.

Key Points

• Ovary is the part of the flower that develops into a fruit after fertilization.
• The ovary contains ovules, which become seeds when fertilized.
• After fertilization, the ovary wall thickens and forms the pericarp, which is the fruit's outer layer.
• The transformation from ovary to fruit ensures the protection and dispersal of seeds.
• This process is crucial for the reproductive cycle of flowering plants, facilitating seed development and propagation.

Additional Information

• The corolla is the collective term for all the petals of a flower, which are usually colorful and attract pollinators.
• Pollen grains are the male gametophytes produced by the anthers of the flower, essential for fertilization.
• The anther is the part of the stamen that produces pollen, playing a key role in the plant's reproductive process.

The correct answer is 1) Plane mirror.

Key Points

• Plane mirrors are the most commonly used mirrors for personal grooming, such as face viewing and makeup application.
• They provide a clear, upright, and undistorted reflection of objects placed in front of them.
• Plane mirrors produce images that are of the same size as the object and maintain the same proportions.
• The image formed by a plane mirror is virtual (not real) and appears to be located behind the mirror at the same distance as the object in front.
• Plane mirrors are used in homes, bathrooms, dressing rooms, and even in optical instruments for basic reflection purposes.

Additional Information

• Concave Mirror:
• Concave mirrors are curved inward and are used to focus light, often in telescopes, headlights, and shaving mirrors.
• They can form both real and virtual images, depending on the object's distance from the mirror.
• When used for face viewing, they magnify the image, making them useful for detailed tasks like shaving.
• Convex Mirror:
• Convex mirrors are curved outward and are primarily used for wide-angle views, like in vehicle side mirrors.
• They always produce virtual, upright, and diminished images, making them unsuitable for face viewing.
• Virtual Image:
• A virtual image is formed when the reflected rays appear to meet behind the mirror.
• Plane mirrors and convex mirrors always form virtual images.
• Reflection of Light:
• The phenomenon of light bouncing back from a surface is called reflection.
• The angle of incidence is always equal to the angle of reflection, as per the law of reflection.

• An apex predator, the tiger is the largest species belonging to the Felidae family. It has been listed on the IUCN Red List as an endangered species.
• Its scientific name is Panthera tigris.

The correct answer is DNA.

Key Points

• DNA stands for Deoxyribonucleic Acid.
• DNA is the hereditary material in humans and almost all other organisms.
• Nearly every cell in a person’s body has the same DNA.
• Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

Additional Information

• Proteins:
• Proteins are large, complex molecules that play many critical roles in the body.
• They are required for the structure, function, and regulation of the body’s tissues and organs.
• Proteins are made up of hundreds or thousands of smaller units called amino acids, which are attached to one another in long chains.
• Carbohydrates:
• Carbohydrates are one of the main types of nutrients and are the most important source of energy for your body.
• Your digestive system changes carbohydrates into glucose (blood sugar).
• Your body uses this sugar for energy for your cells, tissues, and organs. It stores any extra sugar in your liver and muscles for when it is needed.
• RNA:
• RNA stands for Ribonucleic Acid.
• RNA is a polymeric molecule essential in various biological roles in coding, decoding, regulation, and expression of genes.
• RNA, like DNA, is made up of a long chain of components called nucleotides.
• RNA is single-stranded, unlike double-stranded DNA.

The correct answer is Grignard reagent.

Key Points

• When haloalkanes and aryl and vinyl halides react with magnesium metal, they yield Grignard reagents.
• Grignard reagents are of the form RMgX, where R is an alkyl or aryl group and X is a halogen.
• These reagents are essential in organic synthesis for forming carbon-carbon bonds.
• Grignard reagents are highly reactive and can react with a variety of electrophiles to form new compounds.
• The reaction typically occurs in an anhydrous ether solvent to stabilize the Grignard reagent.

Additional Information

• Hinsberg reagent is used to distinguish between primary, secondary, and tertiary amines.
• Tollens' reagent is used to detect aldehydes, where it forms a silver mirror on the test tube.
• Fehling reagent is another test for aldehydes, particularly in distinguishing between aldehydes and ketones.