Explanation

Calcium is an essential mineral found in various foods, including:

• Milk and dairy products (cheese, yogurt)
• Egg shells
• Dark green vegetables (broccoli, kale, spinach)
• Small fish (salmon, sardines) and their bones
• Fortified foods (cereals, juices)

Calcium is crucial for:

• Building and maintaining strong bones and teeth
• Muscle function and contraction
• Nerve function and transmission
• Blood clotting and wound healing

Explanation

• The skin is the outermost layer of the body, covering and protecting the internal organs, muscles, and skeleton.
• It acts as a barrier against external damage, infection, and disease.
• It helps to regulate body temperature, aid in the production of vitamin D, and facilitate the senses of touch and feel.

Explanation

The lymphatics of the intermediate and proximal parts of the urethra and cavernous bodies drain into the internal iliac lymph nodes.

The distal spongy urethra and glans penis drain to the deep inguinal nodes.

Explanation

Allergic rhinitis is an inflammatory condition of the nasal passages caused by an immune response to allergens such as:

• pollen
• dust mites
• animal dander
• mold

Eosinophils are a type of white blood cell involved in allergic responses

And their increased presence in nasal secretions is a hallmark of allergic inflammation.

Explanation

Antiphospholipid antibodies are the risk factor for preeclampsia.

Antiphospholipid syndrome (APS) is an autoimmune disorder

That is associated with pregnancy complications, including:

• preeclampsia
• thrombosis
• autoimmune thrombocytopenia
• fetal growth restriction
• fetal loss
  

Explanation

The most common and widely distributed air pollutant among the options provided is carbon dioxide (CO2).

Carbon dioxide is a naturally occurring gas in the Earth's atmosphere.

Still, human activities, particularly the burning of fossil fuels like coal, oil, and natural gas, have significantly increased its concentration in the atmosphere.

CO2 is a greenhouse gas that contributes to global warming and climate change.

Explanation

Functional residual capacity (FRC), is the volume remaining in the lungs after a normal, passive exhalation.

It is the combination of residual volume (RV) and the expiratory reserve volume

In a normal individual, this is about 3L.

The FRC also represents the point of the breathing cycle

where the lung tissue elastic recoil and chest wall outward expansion are balanced and equal.

Explanation

The health challenges faced by rural communities necessitate a focus on primary healthcare.

This approach aims to meet the basic healthcare needs of individuals and communities in rural areas.

emphasizes:

• preventive care,
• health education,
• early intervention,

Explanation

Zymogen cells, also known as chief cells, are found in the stomach and are responsible for producing and secreting pepsinogen, a precursor enzyme that is converted to pepsin, a digestive enzyme that breaks down proteins.

Explanation

Extracellular signaling in animals can be carried out by:

• Endocrine signaling: This involves the release of hormones into the bloodstream, which then travel to reach distant target cells. Examples include insulin and adrenaline.
• Paracrine signaling: This involves the release of signaling molecules into the extracellular space, which then diffuse to nearby target cells. Examples include histamine and prostaglandins.
• Autocrine signaling: This involves the release of signaling molecules that bind to receptors on the same cell that produced them. Examples include autocrine growth factors.
• Juxtacrine signaling: This involves the release of signaling molecules that bind to receptors on adjacent cells. Examples include signaling through cell-cell contacts.