Zoology

What are Gonads? Definition of Gonads Gonads are reproductive glands in organisms that produce gametes (sperm in males and eggs in females) and secrete sex hormones (such as testosterone, estrogen, and progesterone) essential for sexual development and reproduction. In males, they are called testes, while in females, they are referred to as ovaries. Structure of … Read more

What is Thymus Gland? Definition of Thymus Gland The thymus gland is an important organ of the lymphatic system located in the chest behind the breastbone. It plays a crucial role in the development and maturation of immune cells known as T cells, which are essential for the body’s immune response. The thymus gland is … Read more

What is Pancreas? Definition of Pancreas The pancreas is a vital organ in the human body that serves dual functions: it acts as an endocrine gland by producing hormones such as insulin and glucagon to regulate blood sugar levels, and as an exocrine gland by secreting digestive enzymes and bicarbonate into the small intestine to … Read more

What is Adrenal Gland? Definition of Adrenal Gland The adrenal glands, or suprarenal glands, are small, triangular-shaped endocrine glands located on top of each kidney. They consist of two main parts: the adrenal cortex, which produces steroid hormones such as cortisol and aldosterone, and the adrenal medulla, which produces catecholamines like adrenaline. These hormones play … Read more

What is Parathyroid Gland? Definition of Parathyroid Gland The parathyroid glands are small endocrine glands located behind the thyroid gland that regulate calcium levels in the blood by secreting parathyroid hormone (PTH). This hormone helps maintain calcium balance by influencing the bones, kidneys, and intestines. Anatomical Location of Parathyroid Gland The parathyroid glands are small, flattened, … Read more

What is Thyroid Gland? Definition of Thyroid Gland The thyroid gland is a butterfly-shaped endocrine organ located in the anterior neck that produces hormones such as thyroxine (T4), triiodothyronine (T3), and calcitonin, which regulate metabolism, growth, and calcium homeostasis. It plays a crucial role in maintaining the body’s metabolic rate and overall hormonal balance. Anatomical … Read more

What is Pituitary Gland? Definition of Pituitary Gland The pituitary gland is a small, pea-sized endocrine gland located at the base of the brain, beneath the hypothalamus. It is often termed the “master gland” because it produces and secretes hormones that regulate various bodily functions, including growth, metabolism, and reproduction, and controls the activity of … Read more

What is Pineal Gland? Definition of Pineal Gland The pineal gland is a small, pea-shaped endocrine gland located in the brain, responsible for producing the hormone melatonin, which regulates sleep-wake cycles and circadian rhythms. It responds to light exposure, influencing various biological processes in the body. Location of Pineal Gland Structure of Pineal Gland The structure … Read more