A&P 2 Chapter 13 Learnsmart
What are ways that hormone levels are controlled?
- A gland secretes hormones when it detects that hormone levels are low - The hypothalamus stimulates glands to secrete a hormone
Match the hormones of the adrenal cortex with the factors regulating their secretion
- Aldosterone: Electrolyte concentrations in body fluids - Cortisol: Corticotropin-releasing hormone from hypothalamus and adrenocorticotropic hormone from anterior pituitary
Which hormones are synthesized from amino acids?
- Amine hormones - Protein hormones - Peptide hormones
What hormones are produced by the thyroid gland?
- Calcitonin - Triiodothyronine (T3) - Thyroxine or tetraiodothyronine (T4)
Match the hormone with its effect
- Calcitonin: lowers blood calcium levels - Parathyroid hormone: raises blood calcium levels
There are more than one type of second messenger. What are examples of compounds that serve as second messengers?
- DAG - cAMP - IP3
What are some examples of glycoprotein hormones?
- Follicle Stimulating Hormone (FSH) - Luteinizing Hormone (LH) - Thyroid Stimulating Hormone (TSH)
Match the description with the two major cell types in the thyroid gland
- Follicular cells: Synthesize two hormones and their hormone(s) affect metabolic rates in other cells - Extrafollicular cells: Synthesize one hormone and their hormone(s) affect calcium blood concentration
What are the different features of signal transduction?
- It involves second messengers (biochemicals in the cell that induce changes in response to the hormone's binding) - It involves a first messenger (i.e. a hormone that triggers a cascade of biochemical activity) - It involves binding of a hormone to its receptors on a target cell
What hormones utilize cAMP to produce cellular responses?
- Norepinephrine - Antidiuretic hormone - Calcitonin
The target cells of luteinizing hormone and follicle-stimulating hormone are in what organ(s)?
- Ovaries - Testes
What are examples of peptide hormones?
- Oxytocin (OT) - Somatostatin (SS)
What are some examples of peptide hormones?
- Oxytocin (OT) - Somatostatin (SS)
Match each receptor with the situation in which it would have a role
- Receptor in nucleus: Formation of secondary sex characteristics - Membrane-bound receptor: Running a sprint
What are examples of steroid hormones?
- Sex hormones - Cortisol - Aldosterone - Testosterone - Estrogen
Match the following types of hormones with their composition and examples
- Steroid hormones: formed from cholesterol. They include: estrogen, testosterone, aldosterone, cortisol. - Amine hormones: Formed from amino acids. They include: norepinephrine, epinephrine. - Peptide hormones: Formed from amino acids. They include: antidiuretic hormone, oxytocin, thyrotropin-releasing hormone. - Protein hormones: Formed from amino acids. They include: parathyroid hormone, growth hormone, prolactin. - Glycoprotein hormones: Formed from protein and carbohydrate. They include follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone.
What are some characteristics of lipid-soluble hormones?
- They include steroid hormones - They can diffuse into cells easily
What compounds are classified as nonsteroid hormones?
- glycoproteins - amines
What are some examples of protein hormones?
- growth hormone (GH) - parathyroid hormone
What would cause an increased release of ADH from the pituitary gland?
- increase osmotic pressure in the blood - decrease water intake - decrease blood volume
What are cellular responses to second messenger activation?
- increased membrane permeability - inhibition of metabolic pathways
What are effects of growth hormone?
- increases protein synthesis - stimulates cells to enlarge - stimulates cell division
What are characteristics of the pituitary gland?
- it is located in the sella turcica of the sphenoid bone - it is connected to the hypothalamus by the infundibulum
What are the effects of insulin?
- it promotes movement of glucose into certain cells - it stimulates formation of glycogen from glucose
What mechanisms are triggered when blood glucose is low (for example between meals)?
- pancreatic alpha cells secrete glucagon - increased conversion of glycogen to glucose
What are some effects of glucagon?
- raises blood glucose levels - stimulates the conversion of noncarbohydrates (e.g. amino acids) into glucose - stimulates the liver to break down glycogen
Which are functions of oxytocin?
- stimulates mammary glands to release milk - stimulates uterine muscles to contract
What are characteristics of epinephrine and norepinephrine?
- they are amines - they are derivatives of the amino acid tyrosine
What are the two effects of antidiuretic hormone, or ADH?
- water retention - vasoconstriction
The hypothalamus secretes stimulating or inhibiting hormones that control the release of hormones from the ______ lobe of the _____ gland.
1. Anterior 2. Pituitary
ACTH, FSH, GH, LH, PRL, TSH are produced by the _______ lobe of the pituitary gland, while ADH and oxytocin (OT) are released from the ________ lobe of the pituitary gland.
1. Anterior 2. Posterior
ADH is a(n) ______ that targets the ______, conserving water
1. Antidiuretic 2. Kidneys
The two hormones that are made by the hypothalamus and secreted by the posterior pituitary are ______ hormone and _____
1. Antidiuretic hormone (ADH) 2. Oxytocin (OT)
The conversion of cholesterol to the active form of vitamin D requires several steps. Place the sequence of events in the metabolism of vitamin D in the proper order
1. Cholesterol is converted into provitamin D in the intestine 2. Provitamin D is converted into cholecalciferol in the skin 3. Cholecalciferol becomes hydrocholecalciferol in the liver 4. Hydrocholecalciferol becomes active form of vitamin D in the kidney 5. Active form of vitamin D promotes intestinal calcium absorption
The pancreas works as an ______ gland that secretes digestive juices into the pancreatic duct and as an ______ gland that releases hormones into blood
1. Exocrine 2. Endocrine
Place in the order of sequences of events that occur as a steroid hormones interact with target cells
1. Hormones cross the cell membrane 2. Hormones combine with receptor s 3. Hormone-receptor complexes activate transcription of mRNA 4. In the cytoplasm, mRNA molecules guide synthesis of proteins.
Antidiuretic hormone (ADH) and oxytocin (OT) are synthesized in the ______. Nerve impulses cause their release from the ______ (where they are stored) into the bloodstream
1. Hypothalamus 2. Posterior pituitary
Secretion of growth hormone is ______ by somatostatin (GHIH) and _________ GHRH from the hypothalamus
1. Inhibiting 2. Stimulated Note: recall the 'I' in GHIH mean inhibiting and the 'R' in GHRH means releasing
The result of a hormone binding to a ______ receptor results in an immediate response, while the binding of a hormone to a ______ receptor results in responses that are more long-term
1. Membrane-bound 2. Nuclear
Place in order the sequence of events initiated by some nonsteroid hormones
1. The hormone binds to a receptor 2. G protein is activated and activates adenylate cyclase 3. Adenylate cyclase converts ATP into cyclic AMP 4. cAMP activates proteins kinases 5. Protein kinases phosphorylate substrates 6. Substrates change cellular processes
Hormones are classified into two categories based on their chemical composition, _______ hormones and ______ hormones
1. steroid 2. nonsteroid
Insulin, a nonsteroid hormone, binds with a cell membrane receptor causing activation of proteins inside the cell. What would you consider insulin to be in this example?
A first messenger
How is adrenocorticotropic hormone abbreviated?
ACTH
After a nonsteroid hormone binds to a receptor in the plasma membrane, it activates a G protein, which activates an enzyme that converts ATP into cyclic AMP. What is the name of this enzyme?
Adenylate cyclase
Kari has been experiencing tremendous stress at work lately. It is likely that she will have elevated levels of hormones from her ______ glands in her bloodstream.
Adrenal
Steroids such as aldosterone, cortisol and certain sex hormones are produced by what gland?
Adrenal cortex
What gland produces cortisol and aldosterone?
Adrenal cortex
The adrenal cortex is the target organ of _____
Adrenocorticotropic hormone (ACTH)
What hormone causes the kidneys to conserve sodium ions and water, and to excrete potassium ions.
Aldosterone
Which adrenal cortical hormone(s) have various developmental and reproductive functions?
Androgens
Growth hormone, prolactin, thyroid-stimulating hormone, and others are secreted by what gland?
Anterior pituitary
Where is prolactin produced?
Anterior pituitary (adenohypophysis)
How are steroid hormones transported to their target cells?
Bound to plasma proteins
What are steroid hormones derived from?
Cholesterol
What hormone helps control glucose levels by stimulating the use of noncarbohydrate sources to synthesize glucose and increasing the utilization of fatty acids as an energy source?
Cortisol
What is an example of a second messenger?
Diacylglycerol (DAG)
The general term for any substance that increases urine production is _______
Diuretic
What is the term for a decrease in the number of receptors on a target cell, potentially due to a prolonged increase in the level of a hormone?
Downregulation
What hormones are secreted by chromaffin cells of the adrenal medulla?
Epinephrine and Norepinephrine
A G protein acts as a link between what two chemicals?
First and second messenger
Often, nonsteroid hormones activate a second messenger systems in target cells. In these cases, what is the nonsteroid hormone considered?
First messenger
What hormone functions to stimulate estrogen secretion in the ovary and sperm production in the testes?
Follicle stimulating hormone (FSH)
What is the correct order of activation in a second messenger system using cAMP?
G protein; adenylate cyclase; cAMP; protein kinase
A cellular response to a nonsteroid hormone operating through a second messenger is _______ amplified
Greatly
Chemicals called _______ exert their effects by altering metabolic processes. They may change the activity of an enzyme or alter the rate at which chemicals are transported through cell membranes.
Hormones
Two hormones from the ________ control the secretion of growth hormone from the anterior pituitary gland
Hypothalamus
Where are the receptors for steroid and thyroid hormones usually found?
In the nucleus
As blood calcium concentration drops, PTH levels ______
Increase
What hormone promotes the movement of glucose into cells and stimulates the formation of glycogen from glucose?
Insulin
What is a function of luteinizing hormone?
It stimulates the secretion of sex hormones in both sexes
The adrenal glands are located atop each ______
Kidney
The ______ gland is the target organ of prolactin (PRL)
Mammary
Most hormones are regulated by ______ feedback mechanisms.
Negative
When receptors sense an increase in the concentration of a hormone, signals are sent to decrease the production of that hormone. This is called a _______ feedback mechanism.
Negative
Parathyroid hormone is secreted by the _____ gland
Parathyroid
The gland(s) located on the posterior surface of the thyroid gland is the ______ gland
Parathyroid
What do kinases attach to enzymes?
Phosphates
What inactivates cAMP, thus stopping the cellular response to the second messenger?
Phosphodiesterase
The gland that is made up of an anterior and posterior lobe is the ______ gland
Pituitary
An arrangement of two capillary beds in a series allow for blood to travel from one organ to another without going through the heart first. What is this called?
Portal system
What structure secretes hormone but is actually composed largely of nervous tissue?
Posterior lobe of the pituitary
Which of the following is actually nervous tissue, containing axons?
Posterior pituitary
Mammary glands produce milk in response to stimulation by the hormone
Prolactin
What locally-acting chemicals are derived from arachidonic acid?
Prostaglandins
In order for a hormone to act on a target cell, it must bind to a specific
Receptor
Cyclic AMP (cAMP) molecules are _____ messengers that may be activated by nonsteroid hormones
Second
When activated by a hormone, some target cells produce _______ which then induce the effects of the hormone stimulation within the cell
Second messengers
What is the relationship between steroid hormones and cell membrane?
Steroid hormones can diffuse easily through the cell membrane
The hormone sensitivity of a target cell is determined by what factor?
The presence and number of appropriate receptors
What large-lobed endocrine gland is associated with the larynx in the neck?
Thyroid gland
The thyroid gland is the target organ of which hormone?
Thyroid-stimulating hormone (TSH)
True or false: Hormones are released into the extracellular space surrounding endocrine cells and then diffuse into the bloodstream
True
After a long period of lower than normal hormone concentrations, the target cells might respond by ______ of the receptors
Upregulating
An increase in the number of receptors on a target cell, often in response to a prolonged decrease in the level of a hormone, is called ______
Upregulation
Lipids consisting of complex rings of carbon and hydrogen atoms are ______ hormones
steroid