Science Olympiad Test: Life Processes- 2 - Class 10 Free MCQ with solutions

Autotrophic nutrition is a process where an organism prepares its own food from simple inorganic material like water, mineral salts and carbon dioxide in the presence of sunlight. It is found in plants. The process by which food is prepared is known as photosynthesis which requires carbon dioxide, water, chlorophyll and sunlight.

This is because, the plant-eating animals need to digest cellulose that is present in the plants. Therefore, they have the longest small intestine.

Stomach and pancreas both protein-digesting enzymes. Pepsin is secreted in the stomach by peptic cells in its inactive form- pepsinogen. Pepsinogen gets activated by the hydrochloric acid present in the stomach. Similarly, Trypsin is secreted by the pancreas in its inactive form- Trysogen.

Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy as sugar. 

• Photosynthesis is the process of preparing food in the presence of sunlight and chlorophyll.
• In this process, the plant uses water from the soil, carbon dioxide from the air, and energy from sunlight to prepare glucose.

Carbon dioxide + Water + light energy → Glucose + Oxygen

• During the initial phase of photosynthesis, light energy is harvested to produce ATP and NADPH where water is oxidized to provide electrons and protons.
• After the formation of ATP and NADPH, carbon dioxide is reduced to carbohydrates (glucose)
• The reduction of carbon dioxide to carbohydrates doesn’t directly depend on the presence of sunlight but on the supply of ATP and NADPH that were formed during the initial phase.

Xylem tissues include tracheids, vessels, fibres and parenchyma and serve in the ascent of sap/water and minerals. Phloem tissues is a composed of four elements namely, sieve elements, companion cell, phloem fibres and phloem parenchyma and serve in translocation of organic nutrients. Transfer RNA (tRNA) serve as carrier RNA and transports amino acids from cell pool to the mRNA bound to the ribosome where the protein is being synthesized. Haemoglobin molecule contains four polypeptide chains and four heme prosthetic groups. It serves as a carrier of oxygen gas.

It is so because both have a thick supply of capillaries just under their skin's surface, moist and thin walled marked with dense capillaries for easier diffusion.

• Glycolysis is defined as a sequence of reactions that convert glucose into pyruvate or lactate with the production of ATP (Adenosine triphosphate).
• Pyruvic acid is the end product of glycolysis.
• Two molecules of pyruvic acid are generated by the partial oxidation of one glucose molecule.

• The respiratory system of cockroach consists of a network of the trachea, that open through 10 pairs of small holes called spiracles present on the lateral side of the body. Thin branching tubes (tracheal tubes subdivided into tracheoles) carry oxygen from the air to all the parts. air enters the body through spiracles.
• Tracheae are known to balance the pressure inside the system.
• When oxygen-rich air enters into the body of the cockroach via spiracles into the tracheal tubes, it diffuses into various tissues and cells of the body. Here, oxygen is used up to liberate energy.
• Likewise, carbon-dioxide rich air passes into the trachea and moves to the outwards through the spiracles. Carbon dioxide is given out as a result of the respiratory process.

Mature RBC goes through a process called enucleation just before it enters the blood flow.
Enucleation is an adaptation of the red blood cell which enables it to attain a biconcave structure, increasing room for accomodating more of the haemoglobin leading to greater capacity to carry oxygen molecules. Biconcavity further helps in increasing the surface area for diffusion and agility to squeeze itself through the thin pores of the capillaries to reach oxygen to the tissues.

A sieve plate is a perforated wall between the sieve elements in vascular plants. They are the outer end wall of a sieve-tube element and contain many pores.

Dialysis is the procedure used for cleaning the blood of a person by reparating the waste substance (urea) from it.

Innon-flowering plants tracheids are the only water conducting tissues Tracheids are dead cells with lignified walls with no open ends. They are long, thin and spindle shaped cells. They have pits in them and it is through pits only that water flows from one tracheid to another. All the plants have tracheid in them.

A sphygmomanometer also known as a blood pressure metre, blood pressure gauge, or blood pressure monitor, is a device that monitors blood pressure.

• The sphygmomanometer instrument consists of an inflatable rubber cuff which is applied to the arm.
• This is connected to the mercury column which helps to determine the systolic and diastolic blood pressure.
• It is composes of an inflatable rubber cuff, which is wrapped around the arm.
• A measuring device indicates the cuff’s pressure.
• A bulb inflates the cuff and a valve releases pressure.
• A stethoscope is used to listen to arterial blood flow sounds.

Urea as it is the main excretory waste.

The snake heart has 3 chambers - right and left atria and one ventricle. Hence, the correct choice is (a).