ANSWERS

1. What is a system?
   A collection of tissues and organs which collectively form a specific function.
2. What are the 3 groups into which systems are classified?
   • Structural - concerned with support, transport or movement.
   • Co-ordinating - concerned with communication.
   • Visceral - pertaining to organs contained within the body cavities.
3. Name 2 main features common to the visceral systems.
   • Tubular in design.
   • Possess 1 or 2 openings onto the surface of the body.
4. Name the structural systems and briefly describe their functions.
   • Skeletal system - support and protection of the soft structures of the body.
   • Muscular system - comprised of the voluntary muscle of the skeletal system which is responsible for conscious actions, and involuntary muscle responsible for unconscious actions.
   • Integument - the covering of the body comprising skin, hair (or feathers) and nails.
   • Cardiovascular system (circulatory system) - responsible for the circulation of blood around the body.
5. What is the name of the subgroup of the cardiovascular system which is responsible for the transport of products of digestion from the gut to the liver?
   The hepatic portal system.
6. The lymphatic system is a subgroup of the cardiovascular system and has 5 important roles. Can you name them?
   • Return of excess fluid to the circulation.
   • Filtering bacteria.
   • Filtering foreign substances.
   • Production of lymphocytes.
   • Transport of digested foods (especially fats).
7. What is the name of the subgroup of the cardiovascular system which is responsible for the protection of the body against foreign matter?
   The immune system.
8. Name the co-ordinating systems and briefly describe their functions.
   • Nervous system - receives and interprets information and enables the body to respond.
   • Endocrine system - responsible for communication within the body by chemical messengers called hormones.
9. The special senses are a subgroup of the nervous system. Can you name them?
   • Olfaction (smell).
   • Vision.
   • Hearing & balance.
   • Taste.
10. Name the visceral systems and briefly describe their functions.
    • Digestive system - ingestion and utilisation of food substances and the excretion of waste.
    • Respiratory system - gaseous exchange between animal and environment.
    • Urinary system - removal of waste from the body.
    • Reproductive system - replication.
11. The urinary and reproductive systems are sometimes classified together. What name is given to them under such circumstances?
    The uro-genital system.
12. Name the 3 main body cavities.
    • Thoracic cavity.
    • Abdominal cavity.
    • Pelvic cavity.
13. What is the name of the serous membrane which lines all of the body cavities?
    Serous endothelium.
14. What is the function of the serous endothelium?
    Production of a watery fluid which acts as a lubricant between 2 surfaces.
15. What is the name of the serous membrane that lines the thoracic cavity?
    The pleura (the serous fluid produced is subsequently known as pleural fluid).
16. What is the mediastinum?
    A double layer of pleura that separates the 2 pleural cavities from one another.
17. What bones are covered by the costal pleura?
    The ribs.
18. What organs are covered by the visceral pleura?
    The lungs.
19. List the boundaries of the thoracic cavity.
    • The thoracic inlet (anteriorly).
    • The thoracic vertebrae & hypaxial muscles (dorsally).
    • The sternum (ventrally).
    • The ribs & intercostal muscles (laterally).
    • The diaphragm (posteriorly).
20. What is the name of the serous membrane that lines the abdominal and pelvic cavities?
    The peritoneum (the serous fluid produced is subsequently known as peritoneal fluid).
21. What is the name of the fold of the peritoneum which connects the intestine to the posterior abdominal wall?
    The mesentery.
22. What is the difference between the parietal peritoneum and the visceral peritoneum?
    The parietal peritoneum lines the abdominal cavity and is attached to the body wall, whilst the visceral peritoneum covers the viscera (organs contained within the abdomen).
23. What is the collective name given to the structures responsible for closing the posterior part of the pelvis?
    The pelvic diaphragm.
24. List the boundaries of the abdominal/pelvic cavity.
    • The diaphragm (anteriorly).
    • The sublumbar hypaxial muscles (dorsally).
    • The abdominal muscles and floor of the pelvis (ventrally).
    • The abdominal walls and the lateral wall of the pelvis (laterally).
    • The pelvic diaphragm (posteriorly).