A&P 2 Test 1

Autonomic Nervous System

This part of the nervous system includes both the sympathetic and parasympathetic divisions and innervates smooth muscle, cardiac muscle, and glands in order adjust their activities to achieve homeostasis. It is involuntary.

Sympathetic Division

This division of the ANS is often called the fight or flight division, as it mobilizes the body for activity. It is activated by the 4 E’s, exercise, excitement, emergency, and embarrassment. It sends blood to skeletal muscle and the heart, dilates the bronchioles, and causes the liver to release glucose.

Parasympathetic Division

This division of the ANS is often called the rest and digest division, as it conserves energy and is responsible for the maintenance of bodily systems. It directs the 3 D’s, digestion, diuresis, defecation. The vagus nerve comprises 90% of the nerve fibers of this division.

Spinal Cord and Brainstem

These are the two places in the brain where neurons originate from in the ANS

Thoracolumbar

This is the name given to the sympathetic division of the ANS based on where its neurons originate from

Craniosacral

This is the name given to the parasympathetic division of the ANS based on where its neurons originate

Ganglia

These are clusters of neurosomas and axons, and act as synaptic connection points between neurons

Preganglionic Neuron

This is the name for the first neuron in an ANS pathway in either division, it originates from either the spinal cord or brainstem and synapses with the postganglionic neuron or adrenal gland.

Postganglionic Neuron

This is the name for the second neuron in an ANS pathway in either division. It gets activated from the preganglionic neuron and synapses at the end with an effector.

Close to

Ganglia in the sympathetic division are located _____ the spinal cord

Far from

Ganglia in the parasympathetic division are located ______ the spine

Neurotransmitters and Hormones

The ANS uses ____ as messengers

Acetylcholine

In the sympathetic division this neurotransmitter is sent from preganglionic neurons to postganglionic neurons, while in the parasympathetic system it is sent by both post and preganglionic neurons. It is released by cholinergenic fibers.

Norepinephrine

This neurotransmitter is sent from postganglionic neurons to effectors in the sympathetic division. It is released by adrenergic fibers.

Cholinergic Neurons

This type of neuron releases Acetylcholine.

Adrenergic Neurons

This type of neuron releases Norepinephrine and Epinephrine.

Adrenal Glands

These glands are activated by preganglionic nerve fibers in the sympathetic division to release epinephrine and norepinephrine into the bloodstream as hormones.

Dual Innervation

This term means when an effector is innervated by both the sympathetic and parasympathetic divisions of the ANS. This allows them to act antagonistically or complimentary.

Autonomic Tone

This term refers to the rate of action potentials flowing through the ANS at any given time. The Parasympathetic rate is usually dominant, as it keeps the sympathetic system from going haywire.

Antagonism

This term refers to when regulators have opposite effects on the organ or system they are regulating. This happens a lot with dual innervation in the ANS, and it allows for precise control of visceral activity. It works through different types and numbers of protein receptors.

Reflex Chain

Receptor → Afferent Neuron → Integrating Center (Interneuron) → Efferent Neuron → Effector

Integrating Centers of ANS

Brainstem, Hypothalamus (MOST IMPORTANT), Spinal Cord

Chronic Stress

This is caused by overactivity in the sympathetic division of the ANS, and it can lead to health issues including high blood pressure, digestive problems, and suppression of the immune system. It can be treated by activation of the parasympathetic division.

Endocrine System

This major system of the body uses hormones to communicate and coordinate bodily functions. It is full of glands, tissues, and cells that secrete these hormones.

Gap Junctions

These are pores in the cell membrane that signaling molecules, nutrients, and electrolytes can move through that allow for direct communication between cells.

Neurotransmitters

These are signaling molecules that are released from neurons and travel across the synaptic cleft to bind to receptors on another cell. They have short term effects that set in almost immediately.

Hormones

These are chemical messengers that travel through the bloodstream and bind to distant cells, tissues, and organs. They have long lasting effects that take longer to set in.

Exocrine Glands

This is a category of glands that secrete substances through ducts to the surface of the body. They have extracellular effects, like in food digestion and temperature regulation, and aren’t used for intercellular communication.

Endocrine Glands

This is a category of glands that has no ducts and secretes hormones into the bloodstream. Their secretions have intracellular effects not the target cells.

Steroids

This chemical class of hormones are all derived from cholesterol, with examples being estrogen, testosterone, and cortisol.

Monoamines

This chemical class of hormones are all made from amino acids, with examples being dopamine, epinephrine and norepinephrine, and melatonin.

Peptides/Proteins

This chemical class of hormones is created from chains of amino acids, and examples are insulin, glucagon, and oxytocin

Baroreceptors

Pressure receptors in the body

Nervous System

This major body system contains nerves that provide quick and short reaction to stimuli. It adapts and declines quickly, and it always has a very specific target.

Endocrine System

This major body system uses hormones to produce longer term responses to stimuli. It takes longer to adapt to stimuli, and it can have multiple targets since the hormones travel through the bloodstream.

Steroids

this chemical class of hormones are all derived from cholesterol, and they include sex hormones like estrogen and testosterone, as well as cortico_____ like cortisol that lowers inflammation in the body.

Monoamines

This chemical class of steroids are made of single amino acids, with examples being dopamine, epinephrine and norepinephrine, and melatonin.

Peptides

This chemical class of hormones is made from multiple chains of amino acids, with examples being insulin, glucagon, and oxytocin.

Circadian Rhythm

This is the term used to describe a daily release of hormones

Ovarian Cycle

This is the term used to describe a monthly rhythm of hormone release

Neural Stimuli

This is one of the ways the body stimulates the release of hormones, and it includes nerves signaling an endocrine gland to release the hormones. An example of this is the Adrenal Gland, which is stimulated by a sympathetic division nerve to release epinephrine and norepinephrine.

Hormonal Stimuli

This is one of the ways the body stimulates the release of hormones, and it happens when one hormone binds to a receptor on a gland, signaling the release of another hormone from said gland. An example of this is hormones from the hypothalamus being used to release hormones from the anterior pituitary gland.

Humoral Stimuli

This is one of the ways the body is stimulated to release hormones, and it happens when a certain amount of a substance in the blood is reached, which triggers the release of a hormone. An example of this is insulin being released by the pancreas when too much glucose is in the blood.

Synergistic Effects

This is when multiple hormones act together for a greater effect. An example of this is when FSH and Testosterone work together to produce more sperm than either one would by itself.

Permissive Effects

This is when one hormone has to be present for the other to be able to work. An example of this is in the uterus, where estrogen makes it sensitive to progesterone.

Antagonistic Effects

This is when two hormones have opposite effects on the same cells. This can be seen with insulin and glucagon, where insulin builds and stores glycogen and glucagon breaks down and releases glucose.

Hypothalamus

This is the small part of the brain sitting below the thalamus that controls the pituitary glands.

Anterior Pituitary Gland

This is one of the structures in the pituitary gland, and it is composed of glandular tissue. Six hormones are released from here.

Posterior Pituitary Gland

This is one of the structures in the pituitary gland and it is composed of nervous tissue. An axon transfers two hormones for storage here until they are needed for release. Those are Antidiuretic Hormone and Oxytocin.

FSH: Follicle Stimulating Hormone

This hormone is released by the anterior pituitary gland. In females it stimulates the secretion of sex hormones and the development of the ovarian follicles where eggs reside. In males it stimulates sperm production. It targets the gonads

LH: Luteinizing Hormone

This hormone is released by the anterior pituitary gland. In females it stimulates ovulation, or the release of an egg. In males it stimulates the secretion of testosterone by the testes. It targets the gonads.

TSH: Thyroid Stimulating Hormone

This hormone is released by the anterior pituitary gland. It stimulates the secretion of thyroid hormone in the thyroid gland.

ACTH: Adrenocorticotropic Hormone

This hormone is released by the anterior pituitary gland, and it stimulates the adrenal cortex to secrete glucocorticoids that can get rid of inflammation.

PRL: Prolactin

This hormone is released by the anterior pituitary gland and stimulates the mammary glands to produce milk.

GH: Growth Hormone

This hormone is released by the anterior pituitary gland and causes growth in many tissues and organs.