Human Anatomy and Physiology- Problem Drill 04: Tissues of the Body

Transcription

1 Human Anatomy and Physiology- Problem Drill 04: Tissues of the Body Question No. 1 of 10 A biopsy sample is obtained from a lesion on the right cheek of a male patient. A technician in the histology lab begins to process the sample for histological examination. Based on general sample preparation procedures, which of the following is correct? Question #01 A. The sample can be cut, unprocessed, for a period of up to 24 hrs after harvesting. B. The sample must be preserved with a formaldehyde solution prior to embedding the sample in wax. C. The use of paraffin wax is optional; tissue can also be sectioned carefully, while, fresh with no damage. D. The biopsy sample should be stained with H&E prior to sectioning, to allow better visualization under the microscope. E. None of the answers are correct. The sample must be preserved and processed prior to sectioning to preserve the architecture of the sample. B. Correct! The sample must be preserved with a formaldehyde solution prior to embedding the sample in wax. Paraffin wax must be used, or another stabilizer, to facilitate sectioning of the sample. The first step is to preserve the sample, prior to sectioning and staining. One of the answers is correct. Biological tissues typically do not have the strength and rigidity to allow being cut without disrupting the architecture. In order to facilitate sectioning the sample, it can be embedded in paraffin wax, for example, by placing it in a liquid wax and then allowing it to harden. Prior to embedding the sample for sectioning, it must be preserved or fixed with a formaldehyde solution, then processed or dried with graded alcohols. Tissue samples can then be stained or treated with labeled antibodies for microscopy. Examples of stains commonly used include: (1) H&E, (2) Gram Staining for bacterial identification, and (3) DAPI fluorescent stain to label DNA.

2 Question No. 2 of 10 A 26-year-old male is diagnosed with a connective tissue disease, which affects the connective tissue proper. The patient is given background on his disease and treatment options. Which of the following is correct? Question #02 A. The patient will eventually have mobility problems, as the connective tissue proper includes bone. B. Ligaments and tendons will be affected in the patient, as these are part of the connective tissue proper. C. The adipose tissue will not be affected, as it is not part of the connective tissue proper. D. Areolar tissue, adipose tissue, and muscle tissue could all be affected in this individual. E. Fibrous connective tissue is the only type of connective tissue that could be affected. Bone is not part of the connective tissue proper. B. Correct! Ligaments and tendons could be affected, as these are part of the connective tissue proper. Adipose tissue is part of the connective tissue proper. Areolar and adipose tissue are part of the affected tissue in the patient; however, muscle tissue is not. Fibrous connective tissue, areolar connective tissue, dense connective tissue, elastic connective tissue, and adipose tissue are all connective tissue proper. Connective tissue can be categorized into 3 groups: connective tissue proper, embryonic connective tissue, and specialized connective tissue. Connective Tissue Proper includes: (A) Areolar connective tissue, which includes collagen and elastin fibers; its function is to hold organs and epithelia in place, (B) Dense connective tissue, which forms ligaments and tendons, (C) Elastic connective tissue, which is present in the lining of arteries and gives them their stretch ability in response to blood pressure, and (D) Adipose tissue, which is fat tissue that provides energy storage and insulation.

3 Question No. 3 of 10 A blood sample is sent for haematological testing. The blood sample is prepared for and subjected to microscopy. Based on the components of blood, which of the following is true? Question #03 A. Red blood cells, which transport glucose, were visualized under the microscope. B. Both of the two only types of granulocytes (eosinophils and basophils) were counted and scored for phenotype. C. Eosinophils, which are involved in allergies and certain infections, were assayed during the blood tests. D. Monocytes, which perform cell-mediated immunity, were counted and scored for phenotype. E. All of the 4 cell types that make up the formed elements in whole blood were counted as part of the testing. Red blood cells transport oxygen. There are three types of granulocytes: eosinophils, neutrophils and basophils. C. Correct! Eosinophils are a formed element in blood and they are involved in allergies and certain infections. Monocytes form macrophages in the tissue, and they are part of the inflammatory response. There are 6 different cell types that make up the formed elements in blood: Red blood cells, Lymphocytes (white blood cell), Monocytes, Basophils (granulocyte), Eosinophils (granulocyte), and Neutrophils (granulocyte). Blood contains fluid (plasma) and the following formed elements: (1) Red blood cells, which transport oxygen; (2) Lymphocytes (white blood cells) cell mediated immunity; (3) Monocytes form macrophages in tissues and are in involved in the inflammatory response, (4) Basophils (granulocyte) involved in the inflammatory response, (5) Eosinophils (granulocyte) involved in allergies and certain infections, and (6) Neutrophils (granulocyte) phagocytose microbes during infection.

4 Question No. 4 of 10 A 30-year-old male is given an ultrasound due to a nodule on his thyroid gland. The test revealed an abnormal growth of glandular tissue. Based on the general principles of glandular epithelium, which of the following statements is correct? Question #04 A. Glandular epithelium is specialized for the secretion of hormones. B. Glandular epithelium is a tough, durable form of tissue that provides protection. C. Endocrine glands secrete hormones into ducts or directly onto a free surface. D. Glandular epithelium usually has a low turnover with slow cell renewal. E. Exocrine glands secrete hormones into the bloodstream. A. Correct! Glandular epithelium is specialized for the secretion of hormones. Stratified epithelium is a tough and durable form of tissue; it provides protection in such places as the skin. Endocrine glands secrete hormones into the bloodstream. Glandular epithelium has a high turnover with rapid cell renewal. Exocrine glands secrete into ducts or directly onto a free surface. Glandular epithelium is usually located in the lining of canals and tracts. It is specialized for the secretion of hormones, milk, mucus, sweat and saliva. This type of epithelium usually has a high turnover in the body with rapid cell renewal. A gland is a single cell or a group of epithelial cells adapted for secretion. Endocrine glands secrete hormones into the bloodstream. Exocrine glands secrete into ducts or directly onto a free surface.

5 Question No. 5 of 10 Neural tissue is made up of neurons and the supportive neuroglia. The image below is of a typical neuron. What part of the neuron is labelled with the letter A? (choose the best answer) Question #05 A A. Dendrite. B. Axon. C. Dendritic tree. D. Myelin sheath. E. Both B and D are correct. Dendrites receive incoming impulses, from either other neurons or the cell body. This is correct, but it s not the only correct answer. A dendritic tree is usually attached to the soma or cell body, and it functions by receiving incoming impulses. This is correct, but it s not the only correct answer. E. Correct! The letter A is pointing to the axon of the neuron, which is surrounded with a myelin sheath. Nucleus of the neuron, containing a nucleolus. Cell Body, or Soma - is usually attached to branching dendrites and an axon. Dendrites - receive incoming impulses, from either other neurons or the cell body. Axon transmits neural impulses from the soma to the synaptic terminals. Myelin produced by glial cells speeds up impulse propagation.

6 Question No. 6 of 10 Which of the following cell types myelinate the axons of neurons in the peripheral nervous system? Question #06 A. Astrocytes. B. Oligodendrocytes. C. Ependymal. D. Schwann. E. Satellite. Astrocytes regulate the local environment around the neurons; they do not produce myelin. Oligodendrocytes produce myelin in the central nervous system. Ependymal cells regulate cerebrospinal fluid. D. Correct! Schwann cells myelinate neurons in the peripheral nervous system. Satellite cells are supporting cells in the ganglia as part of the peripheral nervous system. Neuroglia are found in the CNS and PNS. In the CNS, there are: Astrocytes- the most abundant type of glial cell, regulate the external environment of neurons to ensure ions are at correct levels, recycle proteins released by the neurons, and have been called the building blocks of the blood-brain barrier. Oligodendrocytes- wrap around the axons of neurons, a process called myelination. This insulates the neuron so the electrical impulse can travel farther, faster. Ependymal cells - line the cavities of the CNS and regulate cerebrospinal fluid. Microglia- specialized macrophages that protect neurons in the CNS. In the PNS, cells which myelinate neruons are called Schwann cells. Supporting cells in the ganglia are satellite cells.

7 Question No. 7 of 10 A 46-year-old male is given some tests order by his physician. One of the tests was a muscle biopsy. The muscle biopsy revealed a decrease in the number of striations. Based on this information, and the general structure of muscle tissue, which of the following statements is true? Question #07 A. The muscle tested in the biopsy sample is smooth muscle. B. The striations in the muscle tissue are made up of medium-twitch muscle fibers. C. Sarcomeres are the basic unit of contraction in muscle, and they make up the striations. D. The muscle tested is skeletal muscle and it is not under voluntary control. E. Skeletal muscle fibers, which have numerous striations, are made up of 4 different muscle fiber types. Smooth muscle does not have striations. The striations are made up of sarcomeres. C. Correct! Sarcomeres are the basic unit of contraction in muscle, and they make up the striations. Skeletal muscle does have numerous striations, but it is under voluntary control. There are 2 types of muscle fibers in skeletal muscle: (1) slow-twitch, and (2) fast-twitch. Skeletal muscle is found attached to the bones. It provides the force to allow movement of the body. It is striated (with the striations, perpendicular to the muscle fibers) and under voluntary control. Skeletal muscle has striations due to many sarcomeres (basic unit of contraction). Individual muscle myofibrils make up a muscle fiber. There are 2 types of muscle fibers: (a) red (slow-twitch) have more mitochondria and are associated with endurance (b) white (fast-twitch) have fewer mitochondria and are explosive.

8 Question No. 8 of 10 Which of the following statements is correct about cardiac muscle? Question #08 A. Cardiac muscle is striated and under voluntary control. B. Cardiac muscle is totally dependent on the CNS to generate and control the electrical impulses that lead to muscular contraction. C. Pacemaker cells in cardiac muscle are also present in skeletal muscle tissue. D. The intercalated discs in cardiac muscle tissue support the synchronization of muscle contraction in the heart. E. The sinoatrial node located in the central nervous system is key to the regulation of heart muscle contraction. Cardiac muscle is striated but it is not under voluntary control. The pacemaker cells in the sinoatrial node of the heart allow this organ to generate its own heart rate, which can be modulated by the CNS. The pacemaker cells in the heart are only located in the cardiac muscle tissue. D. Correct! The intercalated discs in cardiac muscle tissue support the synchronization of muscle contraction in the heart. The sinoatrial node is located in the right atrium of the heart, and it contains the pacemaker cells. Cardiac muscle is found in the heart. It provides the force that moves blood throughout the body. It is striated, involuntary, has branched fibers, and contains intercalated discs that support the synchronization of the muscle contraction. Cardiac muscle has unique properties: (a) Stimulates its own contraction without the required electrical impulse from the central nervous system (CNS); (b) Special pacemaker cells in the sinoatrial node (located in the right atrium) spontaneously contract and send electrical impulses throughout the heart; (c) Normally, the resting heart rate is between bpm, determined by the pacemaker cells. The CNS doesn t directly create the impulse to contract but modulates it through the autonomic nervous system.

9 Question No. 9 of 10 A patient is diagnosed with a knee condition, which involves the component of the knee joint that is labeled with the letter A in the image below. What is labeled in the image? A Question #09 A. Synovial Membrane. B. Articular Tissue. C. Femur Bone. D. Synovial Fluid. E. Articular Membrane. A. Correct! The synovial membrane is labeled with the letter A in the image. Articular tissue is located on the ends of bones, such as the femur and the tibia bone. The femur bone is in the knee joint, but it is not labeled in the image. The arrow labeled with the letter A is pointing to the synovial membrane that produces synovial fluid. In the knee joint, articular tissue is attached to the ends of the two bones femur and tibia. Femur Bone Synovial Membrane Synovial Fluid Articular Tissue Tibia Bone The synovial membrane covers the surfaces within joints and encloses a space filled with synovial fluid. Synovial fluid is a thick, sticky fluid which reduces the friction between the articular cartilage, provides nutrients, and cushions the joint, such as a knee joint. This membrane contains vast amounts of areolar tissue and squamous epithelial cells, although these epithelial cells do not have a true basal surface.

10 Question No. 10 of 10 A 61-year-old woman goes to her doctor s office because of a large wound on her right leg that she received from a fall. The doctor explains the process of tissue repair to the patient. Based on the principles of tissue repair, which of the following statements is correct? Question #10 A. Tissue repair involves the process of epithelialization. B. There are 5 separate phases in the tissue repair process. C. The inflammatory phase is the final phase of tissue repair, and it can last for up to 1 year. D. During the inflammatory phase, there are no cells that migrate or move into the wound area. This happens in the next phase. E. During contraction, in the proliferation phase, neutrophils are converted to myofibroblasts. A. Correct! Epithelialization takes place during the proliferative phase of tissue repair. There are 3 separate phases in the tissue repair process. The inflammatory phase is the first phase of tissue repair. During the inflammatory phase, neutrophils are attracted to and migrate into the wound area. During contraction, fibroblasts are converted into myofibroblasts. Tissue injury involves different phases of repair that bring new blood vessels to the site, if needed, to deliver the necessary cells and factors. Tissue repair can be divided into the following phases: (1) Inflammatory phase, (2) Proliferative phase, and (3) Remodeling phase.