Answer
Three endocrine glands that are larger or more functional in infants or children than in adults are:
1. **Thymus Gland:** The thymus is relatively larger and more active in infants and children. It plays a crucial role in the development and maturation of T cells, a type of white blood cell important for immune responses. The thymus gradually decreases in size and activity as a person ages, a process known as involution.
2. **Pituitary Gland (Anterior Lobe):** The anterior pituitary gland is more active in children, especially during periods of growth and development. It secretes hormones that regulate various physiological processes, including growth hormone (GH), thyroid-stimulating hormone (TSH), and gonadotropins (LH and FSH). As individuals reach adulthood, the activity of the anterior pituitary decreases.
3. **Pineal Gland:** The pineal gland is relatively larger in children and begins to calcify (accumulation of calcium deposits) as a person ages. It produces the hormone melatonin, which plays a role in regulating sleep-wake cycles (circadian rhythms). The calcification of the pineal gland, also known as pineal gland calcification, is a common occurrence as individuals age.
The term for the shrinkage of a gland with age is **involution**. It refers to the natural reduction in size, activity, or function of an organ or gland over time, often associated with the aging process. Many endocrine glands, such as the thymus and certain parts of the pituitary gland, undergo involution as an individual progresses from childhood to adulthood.
Work Step by Step
Three endocrine glands that are larger or more functional in infants or children than in adults are:
1. **Thymus Gland:** The thymus is relatively larger and more active in infants and children. It plays a crucial role in the development and maturation of T cells, a type of white blood cell important for immune responses. The thymus gradually decreases in size and activity as a person ages, a process known as involution.
2. **Pituitary Gland (Anterior Lobe):** The anterior pituitary gland is more active in children, especially during periods of growth and development. It secretes hormones that regulate various physiological processes, including growth hormone (GH), thyroid-stimulating hormone (TSH), and gonadotropins (LH and FSH). As individuals reach adulthood, the activity of the anterior pituitary decreases.
3. **Pineal Gland:** The pineal gland is relatively larger in children and begins to calcify (accumulation of calcium deposits) as a person ages. It produces the hormone melatonin, which plays a role in regulating sleep-wake cycles (circadian rhythms). The calcification of the pineal gland, also known as pineal gland calcification, is a common occurrence as individuals age.
The term for the shrinkage of a gland with age is **involution**. It refers to the natural reduction in size, activity, or function of an organ or gland over time, often associated with the aging process. Many endocrine glands, such as the thymus and certain parts of the pituitary gland, undergo involution as an individual progresses from childhood to adulthood.
