Explanation

In the five-kingdom system, viruses are not placed in any of the five kingdoms:

1. Monera (bacteria)
2. Protista (eukaryotic organisms)
3. Plantae (plants)
4. Animalia (animals)
5. Fungi (fungi)

Viruses are considered non-living entities.

So, in the five-kingdom system, viruses are not classified in any of the five kingdoms.

Explanation

Vitamin C is found in:

• Citrus fruits like oranges, lemons, and grapefruit
• Other fruits like kiwi, guava, strawberries, and cantaloupe
• Vegetables like peppers, broccoli, Brussels sprouts, and potatoes

Explanation

Eyesight problems, such as hypermetropia, are also known as refractive errors. 

The medical name for long-sightedness is hypermetropia, sometimes called hyperopia.

Long-sightedness leads to problems with near vision (seeing things that are close up) and the eyes may commonly become tired.

Explanation

The breakdown of CFCs releases chlorine, which then acts as a catalyst for the destruction of the ozone layer.

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ND22-1-2023

Explanation

The formation of the primitive streak occurs during the gastrula stage of embryogenesis. 

The primitive streak is a crucial structure that appears at the beginning of gastrulation,

A stage where the three germ layers (ectoderm, mesoderm, and endoderm) are established.

It serves as a pathway for cells to migrate and differentiate into these germ layers

Explanation

The kidneys are responsible for filtering blood and regulating the amount of water and electrolytes excreted in urine.

They can adjust the concentration of urine depending on the body's hydration needs.

This makes them the primary organ for controlling water balance. 

Explanation

 Gonadotropic hormones, like follicle-stimulating hormone (FSH) and luteinizing hormone (LH),

They are specifically secreted by specialized cells called gonadotrophs within the anterior pituitary gland. 

Explanation

(b) How the carbohydrates, proteins, and fats are digested in humans? (5)

Carbohydrates:
Carbohydrates are broken down into glucose by enzymes like amylase in the mouth and small intestine.

Proteins:
Proteins are broken down into amino acids by pepsin in the stomach and proteases in the small intestine.

Fats:
Fats are emulsified by bile and then broken down into fatty acids and glycerol by lipase in the small intestine.

Explanation

Viruses cause typhus.

Typhus is an infectious disease transmitted by fleas or lice, with various types caused by different bacteria.

But the term can sometimes be used loosely in reference to viral infections.

Explanation

Hagfish are marine creatures that possess four hearts.

These hearts pump blood through a series of vessels.

These play a role in maintaining blood pressure and circulation.