BHCS1002 2022/2023

• What are the stages of mitosis in the correct order?

  • Prophase
  • Metaphase
  • Anaphase
  • Telophase
• What percentage of gene loci are individual humans on average heterozygous at?

  Approximately 7%
• How many hydrogen bonds pair adenine to thymine?

  2 hydrogen bonds
• What are Okazaki fragments?

  Short pieces of DNA found on the lagging strand
• In eukaryotes, where does DNA replication take place?

  In the synthesis phase (S)
• What are excised to make mature mRNA?

  Introns
• Which organelle produces microtubules?

  Centrosome
• Which statement is FALSE about the cell membrane?

  It is made up of phospholipid monolayer
• What is the movement of solutes from a region of higher concentration to a region of lower concentration called?

  Diffusion
• Which chemical messengers aid the movement of sperm through the female genital tract?

  Prostaglandins
• When does the foetal stage of development begin?

  At the end of the eighth week
• Where does the cardiac conduction sequence start?

  Sino-atrial node
• Which wave of the ECG represents atrial depolarisation?

  P wave
• What structures prevent individual cardiomyocytes from pulling apart during contraction?

  Desmosomes
• Which substance is a vasoconstrictor?

  Angiotensin II
• What are the functions of the lymphocyte subsets?

  • B lymphocytes produce antibodies
  • T lymphocytes are responsible for cell-mediated immunity
  • NK cells develop in the bone marrow
• Which statement is FALSE regarding hemoglobin?

  Each hemoglobin molecule binds one molecule of oxygen
• Which substance serves as an enzyme in the coagulation of blood?

  Thrombin
• Which muscle is the major expiratory muscle during forced breathing?

  Abdominals
• Where is the maximum carbon dioxide partial pressure normally found in the human body?

  Tissues
• Where does most of the inspired air eventually end up?

  Alveoli
• What is the thick, liquid mixture called when food is mechanically broken down and mixed with gastric secretions?

  Chyme
• Where does peristalsis occur in the digestive tract?

  From the pharynx to the anus
• What do the parietal cells of gastric glands secrete?

  Hydrochloric acid
• In the central nervous system, who forms myelin?

  Oligodendrocytes
• What are the cellular processes of neurons that provide receptive surfaces for input from other neurons?

  Dendrites
• What causes depolarization during an action potential?

  Sodium ions diffusing to the inside of the cell membrane
• What does a motor unit typically include?

  One motor neuron and several muscle fibres
• What do binding sites on the surface of actin allow?

  Formation of cross bridges with molecules of myosin
• What stimulates the release of vasopressin (anti-diuretic hormone) from the posterior pituitary gland?

  Reduced plasma volume
• What is usually accepted as the best overall index of kidney function?

  Glomerular filtration rate
• Which of the following is NOT a function of the endocrine system?

  Generation of nerve impulse
• How is the secretion of hormones from the anterior lobe of the pituitary gland controlled?

  By releasing hormones from the hypothalamus
• Which hormone is released by the posterior lobe of the pituitary gland?

  Antidiuretic hormone
• Which statement is FALSE regarding the skin?

  The subcutaneous layer is between the dermis and the epidermis
• Where are epidermal cells supplied with nutrients from?

  Blood vessels located in the dermis
• Which compartment includes the greatest volume of total body water?

  Intracellular fluid
• How do acid-base buffer systems minimize pH changes?

  By promoting the excretion of hydrogen ions
• How do the kidneys help regulate the pH of body fluids?

  By excretion of hydrogen ions