Medulla Oblongata - Human Biology and Health - Past Exam, Exams of Human Biology

Download Medulla Oblongata - Human Biology and Health - Past Exam and more Exams Human Biology in PDF only on Docsity! Page 1 of 14 ARHOLIADAU EXAMINATIONS SEMESTER 1 EXAMINATIONS 2011 IBERS (BIOLOGICAL SCIENCES) BS12310 HUMAN BIOLOGY AND HEALTH TIME ALLOWED: TWO HOURS ANSWER ALL MULTIPLE CHOICE QUESTIONS ON THE SEPARATE COMPUTER SHEET USE OF CALCULATORS IS ALLOWED INSTRUCTIONS FOR MULTIPLE CHOICE QUESTIONS Answer all multiple choice questions on one optically marked sheet. You must answer each question in the order in which it appears on the question paper. Complete the boxes on the optically marked sheet to give the following details - name, date, subject, module identifier and student number. Student number should be completed by writing the digits in pencil in the top line of the box and then filling in the bar code boxes below with the first digit represented in column 1, the second digit in column 2 and so on. This is done by striking through the little box with a soft pencil as shown in the instructions on the sheet for marking the correct answers. Other instructions are on the sheet, but note the following:- There are five possible answers to each question, only one of them is correct. Record your answers on the optically read sheet by using a soft pencil (HB or softer) to mark the appropriate box thus: Do not tick, cross or ring boxes and do not write elsewhere on the form. 1 mark is given for every correct answer. No marks added/deducted for incorrect answers. No marks added/deducted for blank answers. If you make a mistake on the optically marked sheet, it can be corrected with a soft eraser. Spare sheets are available in the examination hall. Page 2 of 14 1. Which of the following is NOT true regarding the spinal cord? a) Its outer portions are composed of grey matter. b) It is protected by the vertebrae. c) It is involved in reflexes. d) The ascending nerve tracts carry sensory information. e) It transmits nerve impulses between the brain and the rest of the body. 2. Which of the following parts of the brain is used to control skilled activities such as serving in tennis? a) Hypothalamus. b) Pons. c) Cerebellum. d) Thalamus. e) Medulla oblongata. 3. Which one of the following statements is correct concerning neurotransmitters? a) Always cause an excitatory effect on the postsynaptic neuron. b) Are action potentials. c) Cause the release of chemicals from the dendrites of a presynaptic neuron. d) Are stored in vesicles in the axon bulb of a presynaptic neuron. e) Are released into a synaptic cleft in response to a graded potential. 4. Which one of the following is a TRUE statement about the synapse? a) Binding of the neurotransmitter to the postsynaptic neuron results in the release of magnesium into the synaptic cleft. b) Neurotransmitters are stored in the dendrites of the postsynaptic neuron. c) Once released from the post-synaptic neuron, the neurotransmitter will diffuse across the synaptic cleft and bind to the presynaptic neuron. d) Release of a neurotransmitter results in an action potential on the presynaptic neuron. e) The synaptic cleft is a fluid-filled gap located between the presynaptic neuron and the post-synaptic neuron. 5. Which one of the following types of neurons conducts nerve impulses from the central nervous system to organs of the body? a) Sensory. b) Motor. c) Interneurons. d) Both sensory and motor. e) Both sensory neurons and interneurons. 6. Which one of the following hormones regulates water balance? a) Oxytocin. b) Insulin. c) ADH. d) Thyroxin. e) ACTH. Page 5 of 14 19. The organ in which protein digestion begins is the a) mouth b) esophagus c) stomach d) small intestine e) large intestine. 20. Which one of the following hormones is secreted by the stomach in response to the presence of food in the stomach? a) Gastrin. b) Insulin. c) Cholecystokinin. d) Secretin. e) Glucagons. 21. Which of the following is not true regarding the placenta? a) It allows the exchange of nutrients, gases and antibodies between the mother and foetus. b) Alcohol, cocaine and several non-prescription drugs can cross the placenta and enter foetal circulation. c) The placenta is formed solely of foetal tissue. d) The umbilical cord contains blood vessels that connect the placenta to the embryo’s circulation. e) The chorion and chorionic villi of the embryo form part of the placenta. 22. Which of the following is true regarding fraternal twins? a) Result from the union of one egg and one sperm. b) Differ genetically. c) Arise from one zygote. d) Result when the embryonic ball of cells splits into two masses. e) Are also known as conjoined twins. 23. The first 4 days of human embryonic development occur in the a) uterus b) vagina c) cervix d) oviduct e) ovary. 24. A hollow ball of cells made up of a trophoblast, hollow central cavity, and an inner cell mass describes a(n) a) zygote b) morula c) four-cell stage d) embryo e) blastocyst. Page 6 of 14 25. The first point at which the foetus could survive outside the uterus with proper neonatal care is during the _______ month of development. a) eighth b) sixth c) fourth d) seventh e) third. 26. Which of the following is not true regarding skin? a) The stratum basale is the deepest layer of the epidermis. b) The stratum spinosum comprises eight to ten layers of keratinocytes. c) The stratum granulosum contains cells undergoing apoptosis. d) The stratum lucidum contains no keratin and is consequently clear. e) The stratum corneum comprises dead keratinocytes. 27. Which of the following is not a function of skin? a) Production of vitamin D. b) Storage of calcium. c) Protection from dehydration. d) Defence from micro-organisms. e) Regulation of body temperature. 28. Which of the following is true regarding skin? a) The dermis consists of several layers of epithelial cells. b) Keratin is a protein in the cells of the epidermis that prevents the cells from reproducing. c) The skin rests on a layer of connective tissue called the hypodermis. d) The dermis of the skin is primarily composed of fat cells. e) Melanocytes produce calcium which strengthens the skin. 29. Which of the following is NOT associated with the dermis of the skin? a) Melanocytes. b) Oil glands. c) Blood vessels. d) Sensory nerve endings. e) Hair root. 30. Dermal papillae are a) sensory hairs of the epidermis b) invaginations of the dermis c) water repellent granules of the stratum granulosum d) capillaries of the dermis e) ducts from the sweat glands. 31. The amount of blood in an adult human is a) 5L b) 10L c) 1L d) 7L e) 3L. Page 7 of 14 32. Which of the following is not a formed element? a) Red blood cell. b) Plasma. c) White blood cell. d) Platelets. e) Red blood cells and white blood cells. 33. Which of the following plasma proteins is primarily responsible for maintaining an osmotic balance between the extracellular fluid and blood? a) Clotting factors. b) Globulins. c) Haemoglobin. d) Albumins. e) Hormones. 34. Which of the following is not true regarding red blood cells? a) They are produced in the red bone marrow. b) They live approximately 120 days. c) They carry oxygen from the cells to the lungs. d) They contain haemoglobin. e) Aged red blood cells are removed from circulation by cells of the liver and spleen. 35. If a person is blood type O, which of the following antibodies will his body produce? a) Type O antibody. b) Type AB antibody. c) Type A antibody. d) Type B antibody. e) Type A antibody and type B antibody. 36. Which of the following is not a mechanism that assists the veins in returning blood to the heart? a) Valves inside veins. b) High blood pressure associated with the blood in veins. c) Contraction of skeletal muscle surrounding veins. d) Pressure changes in the thoracic and abdominal cavities caused by breathing. e) Effects of the skeletal muscle pump. 37. As blood flows through a capillary, fluid moves from the blood into the extracellular fluid surrounding the cells. Which of the following does not move with this fluid into the extracellular fluid? a) Oxygen. b) Water. c) Nutrients. d) Protein molecules. e) Raw materials needed by the cells. Page 10 of 14 50. Which of the following did not lead to a reduction in environmental resistance and a subsequent increase in carrying capacity for humans? a) Domestication of animals. b) Improved technology. c) Increased incidence of famine. d) Domestication of plants. e) Increased use of tools. 51. Which is the longest bone in the human skeleton? a) Humerus. b) Femur. c) Tibia. d) Radius. e) Ulna. 52. Calcium homeostasis is controlled by the activity of which gland? a) Thyroid. b) Pineal. c) Parathyroid. d) Adrenal. e) Pituitary. 53. What type of tissue is articular cartilage made of? a) Elastic cartilage. b) Flexible cartilage. c) Hyaline cartilage. d) Fibrous cartilage. e) Brown cartilage. 54. Which of the following is not a characteristic of the vertebral column? a) It is the main axis of the body. b) It consists of 33 vertebrae. c) It extends from the skull to the pelvis. d) When viewed from the side the bones form a straight line. e) It is part of the axial skeleton. 55. Points of contact between bones are known as a) fractures b) articulations c) tendons d) reticulations e) osteopores. 56. What is the function of a flexor muscle? a) To bend a joint. b) To straighten a joint. c) To move a body part away from the body midline. d) To move a body part towards the middle of the body. e) To ensure that a joint remains flexible. Page 11 of 14 57. What percentage of skeletal muscle fibres are of the slow oxidative (SO) type? a) Approx. 20%. b) Approx. 30%. c) Approx. 80%. d) Approx. 65%. e) Approx. 50%. 58. What is the expected mortality rate as a result of Clostridium tetani infections? a) 40 to 60%. b) 10 to 30%. c) 20 to 50%. d) 50 to 70%. e) 0 to 20%. 59. Which of the following is NOT true regarding muscle contraction? a) It results in movement. b) Heat is generated. c) Muscles lengthen. d) Body posture is maintained. e) It is followed by muscle relaxation. 60. A skeletal muscle cell a) contains one nucleus b) is usually smaller than other body cells c) has a maximum length of 120mm d) lengthens when its myofibrils shorten e) has myofibrils composed of actin and myosin. 61. What is the approximate residual volume of a normal human lung? a) 5.2L. b) 3.1L. c) 1.2L. d) 0.5L. e) 2.1L. 62. Which of the following is NOT a function of the bronchi and bronchioles? a) Moisten the incoming air. b) Warm the incoming air. c) Compress the incoming air. d) Clean the incoming air. e) Distribute air to the alveoli. 63. What is the total surface area of the alveoli in an average human lung? a) 50m2. b) 10m2. c) 100m2. d) 120m2. e) 75m2. Page 12 of 14 64. The epiglottis and vocal chords are associated with the a) bronchii b) lungs c) pharynx d) larynx e) nasal cavity. 65. Which of the following does not contribute to the distinctive quality of a voice? a) Shape of the vocal cords. b) Nose and nasal cavity. c) Size of lungs. d) Muscles of the pharynx and tongue. e) Teeth. 66. Approximately what percentage of the total water loss from the body per day is by evaporation within the lung? a) 20%. b) 10%. c) 30%. d) 5%. e) 50%. 67. What is the storage capacity of the average human urinary bladder? a) 0.6 to 1.0L. b) 0.2 to 0.5L. c) 0.75 to 1.5L. d) 0.3 to 0.6L. e) 0.4 to 0.7L. 68. What percentage of urea is re-absorbed by the kidney after its initial removal from the blood? a) 10%. b) 100%. c) 20%. d) 50%. e) 75%. 69. Which of the following is not normally excreted in the urine? a) Excess ions. b) Cellular waste products. c) Vitamins. d) Proteins. e) Drugs.