Questions with Verified Solutions
What is an endocrine gland? - A ductless gland that secretes hormones into the
bloodstream; for example, the thyroid and adrenal glands.
Where are endocrine glands located? - The hypothalamus, pituitary gland, & pineal
gland. Thyroid & parathyroid, adrenals, pancreas, thymus, gonads (ovary/testis). Hormones are
also secreted by numerous organs and tissues not usually thought of a glands, brain, heart,
small intestines, bones, muscles, and adipose tissue.
What is the primary type of tissue that makes up these structures? (Endocrine) -
Epithelial tissue
What do these endocrine glands do? - secrete hormones into the bloodstream to
maintain homeostasis
Role of endocrine system - Regulating growth and development
What is a hormone? - a hormone is a chemical signal found in multicellular organisms.
interact with target cells and travel in body fluids.
How do hormones affect other tissues? - Hormones can be thought of as chemical
messages
The hormone can also create changes in the cells of surrounding tissues (paracrine effect)
What has to occur at the target tissue for the hormones activity to be carried out? -
Hormones must first interact with an appropriate receptor located either on plasma
membrane or inside of cell. Receptors located in plasma membranes of target cells. Hormones
that bind to receptors in plasma membrane cannot directly affect activities inside target cells.
How do the hypothalamus know when to secrete one of its hormones? - Nerve cells in
the hypothalamus make chemicals that control the release of hormones secreted from the
pituitary gland. The hypothalamus gathers information sensed by the brain and send it to the
pituitary.
Hypothalamus - brain region controlling the pituitary gland
Growth hormone-releasing hormone (GHRH) - promotes the release of growth hormone
from pituitary gland