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56 terms

Chapter 45

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hormones
Animal ___ are chemical signals that are secreted into the circulatory system and communicate regulatory messages within the body. For an example, they control insect metamorphosis.
endocrine, nervous
Two systems coordinate communication throughout the body: the ___ system and the ___ system.
endocrine
The ____ system secretes hormones that coordinate slower but longer-acting responses including reproduction, development, energy metabolism, growth, and behavior.
nervous, neurons
The ____ system conveys high-speed electrical signals along specialized cells called ___; these signals regulate other cells.
target cells
Chemical signals bind to receptor proteins on ____. Only these can respond to the signal.
signaling molecules
Hormones, local regulators, neurotransmitters, neurohormones, and pheromones are types of what?
endocrine signals
_____ (hormones) are secreted into extracellular fluids and travel via the bloodstream.
endocrine glands
_____ are ductless and secrete hormones directly into surrounding fluid.
growth, development, reproduction
Hormones mediate responses to environmental stimuli and regulate ___, ___, and ___.
exocrine glands
In contrast to endocrine glands, ____ have ducts and secrete substances onto body surfaces or into body cavities; e.g. tear ducts.
local regulators
____ are chemical signals that travel over short distances by diffusion. They help maintain blood pressure, nervous system function, and reproduction.
paracrine, autocrine
Local regulators are divided into two types: ___ signals act on cells near the secreting cell, and ___ signals act on the secreting cell itself.
synapses, neurotransmitters
Neurons (nerve cells) contact target cells at ___. At these, neurons often secrete chemical signals called ____ that diffuse a short distance to bind to receptors on the target cell.
sensation, memory, cognition, movement
Neurotransmitters play a role in ____, ____, ____, and ____.
neurohormones
___ are a class of hormones that originate from neurons in the brain and diffuse through the bloodstream.
pheromones
____ are chemical signals that are released from the body and used to communicate with other individuals in the species. They mark trails to food sources, warn of predators, and attract potential mates.
polypeptides, amines, steroids
Three major classes of molecules function as hormones in vertebrates: ____, ____, and ____.
insulin, epinephrine
The two water soluble molecules that function as hormones are ____ (a polypeptide) and ____ (an amine).
cortisol, thyroxine
The two lipid soluble molecules that function as hormones are ____ (a steroid) and ____ (an amine).
lipid
The binding of a ___-soluble hormone to a receptor on a cell leads directly to gene regulation in the nucleus, which eventually leads to a cytoplasmic response. These hormones can easily pass through membranes.
water
The binding of a ___-soluble hormone to a receptor on a cell lead either to gene regulation in the nucleus or to a cytoplasmic response. These hormones cannot easily pass through membranes.
receptors
The solubility of a hormone correlates with the location of ____ inside or on the surface of target cells.
thyroxine
____ in frogs promotes resorption of the tadpole's tail in addition to regulating metabolism.
receptors, pathways, proteins
The same hormone may have different effects on target cells that have different ___ for the hormone, different signal transduction ____, or different ____ for carrying out the response.
endocrine
Negative feedback and antagonistic hormone pairs are common features of the _____ system.
regulatory pathways
Hormones are assembled into ____.
endocrine glands
The hypothalamus, pineal gland, pituitary gland, thyroid gland, parathyroid glands, adrenal glands, kidneys, pancreas, and ovaries are all examples of major ____.
heart, liver, thymus, stomach
Name four organs that contain endocrine cells.
negative feedback
A ___ loop inhibits a response by reducing the initial stimulus. It regulates many hormonal pathways involved in homeostasis.
90, 100
At homeostasis, as blood glucose level should be ___mg/___mL
beta
The __ cells of the pancreas release insulin into the blood.
liver
The ___ takes up glucose and stores it as glycogen.
glucagon
The alpha cells of the pancreas release _____.
insulin, glucagon
____ and ____ are antagonistic hormones that help maintain glucose homeostasis.
islets of Langerhans
The pancreas has clusters of endocrine cells called ____ with alpha cells that produce glucagon and beta cells that produce insulin.
uptake, breakdown, fat
Insulin reduces blood glucose levels by promoting the cellular ___ of glucose, slowing glycogen ____ in the liver, and promoting ___ storage.
fat, protein
Glucagon increases blood glucose levels by
Stimulating conversion of glycogen to glucose in the liver and stimulating breakdown of ___ and ___ into glucose.
diabetes mellitus
___ is the best-known endocrine disorder. It is caused by a deficiency of insulin or a decreased response to insulin in target tissues. It is marked by elevated blood glucose levels.
one
Type ___ diabetes mellitus (insulin-dependent) is an autoimmune disorder in which the immune system destroys pancreatic beta cells.
two
Type ___ diabetes mellitus (non-insulin-dependent) involves insulin deficiency or reduced response of target cells due to change in insulin receptors.
nervous system
Signals from the ____ initiate and regulate endocrine signals.
ecdysone
In insects, molting and development are controlled by a combination of hormones: A brain hormone stimulates release of ___, a molting hormone, from the prothoracic glands.
juvenile hormone
In insects, molting and development are controlled by a combination of hormones: ____ promotes retention of larval characteristics.
hypothalamus
The ____receives information from the nervous system and initiates responses through the endocrine system.
pituitary gland
Attached to the hypothalamus is the ____, which is composed of the posterior pituitary and anterior pituitary.
posterior
The ____ pituitary stores and secretes hormones that are made in the hypothalamus.
anterior
The ____ pituitary makes and releases hormones under regulation of the hypothalamus.
hormone cascade
A hormone can stimulate the release of a series of other hormones, the last of which activates a nonendocrine target cell; this is called a ____ pathway. These are regulated by negative feedback.
thyroid
The release of ___ hormone results from a hormone cascade pathway involving the hypothalamus, anterior pituitary, and thyroid gland.
tropic hormone
A ____ regulates the function of endocrine cells or glands. The four strictly tropic hormones are: Thyroid-stimulating hormone (TSH), Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), and Adrenocorticotropic hormone (ACTH).
nontropic hormones
A ____ targets nonendocrine tissues. Nontropic hormones produced by the anterior pituitary are: Prolactin (PRL) and Melanocyte-stimulating hormone (MSH).
anterior pituitary
Nontropic hormones are produced by the ____.
endocrine signaling
____ regulates metabolism, homeostasis, development, and behavior.
parathyroid hormone, calcitonin
Two antagonistic hormones regulate the homeostasis of calcium (Ca2+) in the blood of mammals: ____ (PTH) is released by the parathyroid glands and ____ is released by the thyroid gland.
10, 100
At homeostasis, the blood Ca^2+ level is about ___mg/__mL.
bones, kidneys
When the blood calcium level decreases, the parathyroid gland either stimulates calcium release from the ___ or it stimulates calcium uptake in the ____-->vit D then increases calcium uptake in the intestines.