Biology

RBCs stands for Red Blood Cells, which are scientifically called Erythrocytes. The other options are incorrect as Leucocytes are white blood cells, Nucleotides are building blocks of nucleic acids, and AOT is unrelated.

Oxygen makes up about 65% of the human body's mass, primarily because water (H2O) is a major component of the body. The other elements are present in smaller percentages.

Leukemia is a type of cancer that affects blood and bone marrow and does not form solid tumors, unlike the other cancers listed which typically form tumors.

White Blood Cells (WBCs) are also known as leukocytes, which are cells of the immune system involved in protecting the body against infections. Lymphocytes are a type of WBC, nucleotides are building blocks of nucleic acids, and erythrocytes are red blood cells.

The normal human body temperature is approximately 37 °C, which the body maintains despite minor fluctuations due to homeostasis.

Trachoma is a bacterial infection that affects the eyes, causing roughening of the inner surface of the eyelids and potentially leading to blindness if untreated. The other options are unrelated to bacterial eye diseases.

The liver is the largest gland in the human body, responsible for many vital functions including detoxification, protein synthesis, and production of biochemicals necessary for digestion.

Tetanus is caused by the bacterium Clostridium tetani, making it a bacterial infection. It is not caused by viruses, fungi, or parasites.

Blood is a tissue composed of cells suspended in plasma, making it a connective tissue. Lungs, kidney, and pancreas are organs, not tissues.

Prolactin is the hormone responsible for stimulating milk production in the mother's breast. Oxytocin, while important for milk ejection, does not initiate milk production. FSH and ADH are unrelated to lactation.

The outermost layer of human skin is called the epidermis. It serves as a protective barrier against environmental factors.

Parkinson's disease primarily affects the brain, specifically the neurons that produce dopamine, leading to motor control issues. It is not related to the eyes, heart, or lungs.

The human eye is often estimated to have a resolution roughly equivalent to about 570 megapixels, based on the density of photoreceptors and the field of view. This makes option A the closest and most accepted estimate among the choices.

Plasma constitutes about 55% of human blood by volume, making option B the correct answer. The other options are either too low or too high compared to the accepted average percentage.

Tuberculosis is caused by the bacterium Mycobacterium tuberculosis, making it a bacterial infection.

Dr. James Watson, along with Francis Crick, discovered the double helix structure of DNA in 1953, which is a well-documented historical fact in molecular biology.

The gestation period of mice is approximately 3 weeks (around 19 to 21 days), making option C the correct choice.

Most owls are nocturnal hunters, meaning they primarily hunt during the night when their prey is active and their vision and hearing are most effective.

Aphasia is a condition characterized by the loss or impairment of the ability to communicate, typically due to brain injury or stroke. Therefore, the inability to communicate is the correct description of aphasia.

Karl Landsteiner discovered the ABO blood group system in 1901, which was a groundbreaking finding in immunology and transfusion medicine. This discovery allowed for safer blood transfusions by matching compatible blood types.

Xerostomia is the medical term for dry mouth, which occurs due to reduced or absent saliva flow. This condition is commonly recognized and distinct from dryness of skin, nose, or head.

Cockroaches can survive for weeks without their heads because their brains are not essential for basic bodily functions like breathing and circulation, which are controlled by nerve centers in their body segments. Other insects listed do not have this capability.

Carpology is the study of seeds and fruits, focusing on their structure, development, and classification. This makes option C the correct answer.

The optic nerve is known as the second cranial nerve because it is the second of twelve cranial nerves and is responsible for transmitting visual information from the retina to the brain.

ATP (adenosine triphosphate) is known as the energy currency of the cell because it stores and provides energy for many cellular processes. The other options are incorrect as fat is an energy storage molecule, lead is a toxic metal, and 'None of These' is not applicable.