Explanation

• The Ear is made up of both internal and external parts.
• The external part is the visible outer ear.
• The internal parts include the middle ear and the inner ear.
• Which contain the cochlea and the vestibular system.

Explanation

• Most headaches are caused by irritation or inflammation of the nerves in the head and neck, rather than the brain itself.
• This can be due to various factors such as tension, stress, or medical conditions.

Explanation

Long bones are found in:

• the arms (humerus, ulna, radius)
• legs (femur, tibia, fibula),
• fingers (metacarpals, phalanges) 
• toes (metatarsals, phalanges)
  

Explanation

• Flukes (trematodes) and tapeworms (cestodes) are both types of parasitic flatworms (Platyhelminthes).
• They have a well-developed reproductive system, which allows them to produce large numbers of eggs and reproduce effectively in their host organisms.

Explanation

• Down's syndrome, also known as Trisomy 21, is a genetic disorder caused by the presence of an extra copy of chromosome 21.
• This occurs due to a process called nondisjunction, where the chromosomes fail to separate properly during cell division (meiosis), resulting in an extra copy of chromosome 21 being inherited.

Explanation

• Cell signaling refers to the process by which cells communicate with each other and respond to their environment. It involves the transmission and reception of signals, which can occur through both intercellular and intracellular pathways.
• Intercellular signaling refers to the communication between different cells, where signals are transmitted through the extracellular space, such as through hormones, neurotransmitters, or other signaling molecules.
• Intracellular signaling refers to the communication within a cell, where signals are transmitted through various signaling pathways, such as protein-protein interactions, phosphorylation cascades, and gene regulation.

Explanation

Vitamin D is found in:

• Milk (fortified milk and dairy products)
• Cod liver oil (and other fatty fish oils)
• Sunlight (our bodies produce vitamin D when exposed to sunlight)

Additionally, vitamin D is also found in:

• Fatty fish (like salmon, mackerel, and sardines)
• Fortified cereals and orange juice
• Egg yolks
• Mushrooms (some types, like shiitake and portobello)

Explanation

Circinate vexation refers to the coiled arrangement of young leaves (usually in ferns) where the tip is rolled inward.

As the leaf matures, it gradually unrolls — a unique characteristic of fern leaves (fronds).

Explanation

Interstitial cells, specifically Leydig cells in the testes, secrete androgens, primarily testosterone, in response to stimulation by luteinizing hormone (LH).

These hormones are crucial for the development of male secondary sexual characteristics and overall reproductive function. 

Explanation

Excess melanin-stimulating hormone (MSH) is secreted in Addison's disease

Because the adrenal glands are not producing enough cortisol

Which leads to an increase in ACTH (adrenocorticotropic hormone)

Which in turn stimulates the production of MSH, resulting in hyperpigmentation (darkened skin).