exam 4 review questions
(b) list the hormones secreted by each of these glands
- the hormones secreted by the anterior pituitary gland are the human growth hormone, thyroid-stimulating hormone, follicle stimulating hormone, luteizing hormone, prolactin, adrenocomcotropic hormone, and melanocyte - stimulating hormone. The posterior lobe of the pituitary gland secretes oxytocin, and antidiunetic hormones. The thhyroid gland secretes trilodothyronine, thyroxine, and calcitonin. The parathyroid gland secretes parathyroid hormones. The adrenal glands secrete steroid hormones, and epinephrine and norepinephrine. The pineal gland secretes melatonin
Compare and contrast each of the following pairs of terms: (a) circulatory system and cardiovascular system,
A circulatory system is divided into the cardiovascular system and the lymphatic system. The cardiovascular system is composed of the blood, the heart, and the blood vessels.
Trace a drop of blood through all the heart chambers and heart valves, and through the basic vascular circuits, from the time it enters the left atrium until it returns to the left atrium again.
A drop of blood goes through the superior vena cava, to the inferior vena cava, coronary sinus, through the right trim, through the tricuspid valve, right ventricle, and through the pulmonary semilunar valve, and out through the pulmonary trunk. When the blood passes to the lungs, oxygen rich blood returns through the pulmonary veins, into the left atrium, through the mitral valve, into the left ventricle, through the aortic semilunar valve, and out through the aorta.
5. Differentiate between arteriosclerosis and atherosclerosis.
Arteriosclerosis is the stiffening or hardening of the artery walls. Atherosclerosis is the narrowing of the artery because of plaque build-up. Atherosclerosis is a specific type of arteriosclerosis.
Which is more resistant to fatigue, cardiac muscle or skeletal muscle? What is the anatomical basis for this difference, and why is it important?
Cardiac muscle is more resistant to fatigue. Cardiac muscle contain a great abundance of mitochondria surrounding the branches of myofibrils. The large abundant of mitochondria make large amounts of ATP by aerobic metabolism. This is important because our heart is consistently beating.
(b) complete blood count and complete blood count with differential.
Complete blood count quantifies the various blood cells and measures some basic aspects of blood chemistry, providing a preliminary assessment of a patient's health. A complete blood count with differential includes the examination of living white and red cells under a microscope for structural abnormalities.
Distinguish among elastic arteries, muscular arteries, and arterioles relative to their location, histology, and functions.
Elastic arteries are the large, thick-walled arteries close to the heart. They have generous amounts of elastic tissue in all tunics, but especially in the tunica media. This elastic tissue enables them to withstand large pressure fluctuations by expanding when the heart contracts, forcing blood into them. They recoil as blood flows forward into the circulation during heart relaxation. They also contain substantial amounts of smooth muscle but are relatively inactive in vasoconstriction. Muscular arteries are medium-sized, and smaller arteries, farther along in the circulatory pathway, carry blood to specific body organs. Their tunica media contains proportionately more smooth muscle and less elastic tissue than that of elastic arteries, but they typically have an elastic membrane on each face of the tunica media. They are more active in vasoconstriction and are less distensible. Arterioles are the smallest of the arterial vessels. The smallest—terminal arterioles—feed directly into the capillary beds. The larger arterioles exhibit all three tunics and their tunica media is chiefly smooth muscle with a few scattered elastic fibers. The walls of the smaller arterioles are little more than smooth muscle cells that coil around the tunica intima lining. When arterioles constrict, the tissues served are largely bypassed; when the arterioles dilate, blood flow into the local capillaries increases dramatically.
Aparna, a gross anatomist who has been teaching human anatomy for 35 years, told her class that in adults the thymus is atrophied and has no function. Is she correct? Explain.
Even though the thymus atrophies over time, it continues to produce immunocompetent T cells through out adulthood, but at a reduced rate. The anatomy teacher is correct to tell the students that the thymus atrophies in adults, but is incorrect in saying that it is nonfunctional.
What are the functions of the following; plasma proteins, globulins, albumin, fibrinogen?
Globulins contain antibodies and blood proteins that transport lipids, iron, and copper. Albumin helps keep water from diffusing out of the bloodstream into the extracellular matrix of tissues. Fibrinogen is one of several molecules involved in a series of chemical reactions that achieves blood clotting. These are all examples of plasma proteins.
Describe the structure and function of an intercalated disc.
Intercalated discs are complex junctions that join cardiac muscle cells. The sarcolemmas of adjacent cells interlock through meshing "fingers". There are two distinct regions: transverse region that contain desmosome-like junctions that bind adjacent cells together, and longitudinal regions that contain gap junctions that allow ions to pass between cells.
(b) Is the conducting system made of nerves? Explain.
No, the conducting system is made up of a series of specialized cardiac muscle cells that carry impulses throughout the heart musculature, signaling he heart chambers to contract in the proper sequence.
How does plasma differ from serum?
Plasma is a straw colored, sticky fluid that is 90% water, and contains over 100 different kinds of molecules including ions such as sodium, and chloride. Serum is plasma from which the clotting factors have been removed.
(a) describe where in the body each of the following endocrine lands are located: anterior and posterior lobe of the pituitary, pineal, thyroid, parathyroid, and adrenal
The anterior lobe of the pituitary gland is located behind the nose, near the underside of the brain. The posterior lobe of the pituitary gland is located off the bottom of the hypothalamus at the base of the brain, resting in a small bony cavity. The pineal gland is located on the back portion of the third cerebral ventricle of the brain. The thyroid gland is a butterfly-shaped gland that sits on the front of the neck, below the Adam's apple, along the front of the windpipe. The parathyroid are located in the neck behind the thyroid. The adrenal glands are located on top of the kidneys
Which class or classes of formed elements form the buffy coat in a centrifuged blood sample?
The buffy coat is a thin gray layer that is between erthycotes and the plasma. It contains leukocytes, and platelets.
Which of these features is absent from brain capillaries in the blood-brain barrier?
The capillaries in the brain lack the structural features responsible for the capillary permeability. These features include: the brain capillaries are continuous in nature. They lack fenestrations and have complete tight junctions. There are no intercellular clefts, and only important molecules are allowed to enter the brain tissue from the capillaries. These molecules are taken through selective transport mechanisms in the plasma membrane o the endothelial cells.
(a) What structural features are responsible for the permeability of capillary walls
The capillary wall is thin and made up of a single layer of endothelial cells. This allows direct diffusion of molecules such as gasses, nutrients, and waste products through the capillary wall. The endothelial cells can form pinocytotic vesicles by invagination of the plasma membrane. There are tight junctions and desmosomes between the endothelial cells. The tight junctions do not allow the transport of small molecules. Along with the junctions there are gaps between the cells called as the intercellular clefts. The intercellular clefts allow the passage of small molecules.Some capillaries are fenestrated and have pores in the endothelial cells. These allow rapid exchange of small molecules between good and the tissue fluid.
(c) What are the functions of this conducting system?
The conducting system carries impulses throughout the heart musculature, signaling the heart chambers to contract in the proper sequence.
When Joshua explained to his classmate Jennifer that the thyroid gland contains parathyroid cells in its follicles and that the parathyroid cells secrete parathyroid hormone and calcitonin, jennifer told him he was all mixed up again. Correct Josh's mistakes
The correction in Josh's mistake is that the thyroid gland contains follicular cells and the thyroid gland contains follicular cells and the parafollicular cells, not the parathyroid cells. These parafollicular cells secrete the hormone, calcitonin. Parathyroid cells are present in parathyroid glands that secrete parathyroid hormone. Parathyroid hormone and calcitonin are opposite in their functions
What are the ductus venous and ductus arteriosis, where are they located, what are their functions, and how are they different?
The ductus venous is a fetal blood vessel that acts as a shunt and connects the umbilical vein to the inferior vena cava, it is located between the umbilical vein and the inferior vena cava. In postnatal life the remnant of ductus venous is ligament venous on the inferior surface of the liver. The ductus venous shunt allows the blood from the umbilical vein to flow into the hepatic veins, inferior vena cava, and finally to the right atrium of the heart. The ductus arterioles is a fetal blood vessel that acts as a shunt and connects the pulmonary trunk and the aortic arch. It is located between the pulmonary trunk and the aortic arch. This blood vessel allows the blood to bypass the pulmonary circuit.
(a) Name the elements of the heart's conducting system, in order, beginning with the pacemaker.
The elements of the heart's conducting system begins with the pacemaker or sinoatrial node, which then spreads in a wave along the cardiac muscle fibers of the atria, signaling the atria to contract. Some of these impulses travel along an internal pathway to the atrioventricular (AV) node. They are delayed for a fraction of a second, then go through the AV bundle, which then enters the inter ventricular septum which terminate in the subendocardial conducting network, or Purkinje fibers, which then approach the apex of the heart and then turn superiorly into the ventricular walls.
Compare and eosinophil to a basophil, both in structure and function.
The eosinophils are responsible for tuning off allergic responses and killing parasites. They can be found in the wall of the digestive tube. Basophils are responsible for releasing histamine and other mediators of inflammation. These cells arise from distinct lines of immature cells in the bone marrow.
How do the right and left ventricles differ structurally, and how do these structural differences reflect functional differences?
The left ventricle is thicker and more muscular than the right ventricle because it pumps blood at a higher pressure. The right ventricle is triangular in shape and extends from the tricuspid valve in the right atrium to near the apex of the heart.
Explain the basic functional differences between B and t lymphocytes
The main basic functional differences between B cells and T lymphocytes are that T cells can only recognize viral antigens outside the infected cells, and B cells can recognize the surface antigens of bacteria and viruses.
list the hormones secreted by each of the three zonas of the adrenal cortex
The outer zona glomerulosa synthesizes and secretes mineralocorticoids. The middle zona fasciculata secretes glucocorticoids. he inner zona reticularis produces androgenic steroids and some glucocorticoids.
If you saw a blood vessel and a collecting lymphatic vessel running side by side, how could you tell them apart?
There are some physical differences between blood vessels and lymphatic vessels. Blood vessels are red in color because they carry the red colored blood. The blood in arteries is red as it is oxygenated. Blood in veins is deep or dark red and not blue. Blood vessels form a closed circulatory system. Lymphatic vessels are colorless or pale white because they carry the pale yellow colored fluid called lymph. A lymphatic vessel appears like a string of beads. This is because the bas of each valve in a lymphatic vessel is bulged and forms a pocket that appears like a bead. One end of lymphatic vessels (capillaries) is open. They form an open circulatory system.
(a)Name an organ containing fenestrated capillaries.
These capillaries are found in the small intestine. They absorb digested nutrients. The fenestrated capillaries are also present in glomeruli of the kidneys that filter blood. The capillaries in the synovial membrane of joints are also fenestrated. They allow the exit of water molecules to the synovial fluid.
(b) What is a sinusoid?
They are capillaries that are wide and leaky. They have few cell junctions. The intercellular clefts may be wide and allow exchange of large materials including cells. These capillaries may have twisted course that slows the blood flow and allows time for exchange of materials.
As George was reading this chapter for the second time, he suddenly had an insight, exclaiming, "Lymph comes from the blood and then it returns to the blood!" Is this insight correct? Explain.
This insight is correct. The lymphatic vessels drain into larger lymphatic ducts that finally empty into venous circulation. In this way, excess tissue fluid collected by lymphatic vessels is returned to the blood stream. So, lymph arises from blood and is finally returned to the blood by the lymphatic system.
List and briefly explain three important functions of the lymphatic vessels.
Three main functions of lymphatic vessels include: return fluid to the bloodstream, absorb fat and fat solute vitamins from the intestines, and defends the body against disease.
(a) define hormone
a hormone is a regulatory substance produced in an organism and transported in tissue fluids such as a blood or sap to stimulate specific cells or tissues into action
(b) name ahormone secreted by a muscle cell and a hormone secreted by a neuron
a hormone that neurons secrete is oxytocin, and a hormone that muscle cells secrete is atrial natriuretic peptide
The anterior lobe of the pituitary secretes so many hormones it is often called the master endocrine organ, but it too has a "master". What structure controls the release of anterior pituitary hormones
the hypothalamus regulates the hormone secretion
