Biology Study Set 13
Quiz 37 :
The child brought for treatment has a history of OI, which includes, breathing difficulty, hearing impairment, brittle teeth; all caused by the underlying reason a mutant gene. OI means osteogenesis imperfecta where the gene that codes for the collagen in bones has mutated. Children affected show all or some of these symptoms- short stature, weak and loose joints, easy bruising and bleeding, fragile skin, weak muscles, etc. This is not a disease caused due to malnutrition, lack of calcium, or child abuse, but deformed bones since birth due to a mutant collagen gene. A skin or blood sample can tell about the amount of collagen present and a DNA analysis can say about the child's genetic condition.
Bones are reservoirs of minerals like calcium and phosphorous ions. Each deposit and withdrawal maintains the ionic concentration in body fluids. The wear and tear of bones and their strength is maintained by the movement of ions in and out of them. Bones anchor and support the muscles. Only skeletal muscles are the functional partners of bones. These muscles move and work only with the help of the bones or the skeletal system. Besides, these bones are the site of blood cell formation, though not all bones, some are specialized for this. Hence, option D is correct as all the options from A to C are true.
When training for a marathon a person is required to be disciplined in all aspects and areas. This includes intake, practice, exercise, and rest. Only if all these are followed can a person be a good sportsman. If miss L is my friend and consults me regarding creatine supplements to enhance athletic energy, I would not recommend it. She should be a good sportswoman and do justice to sports and not cheat herself and the other competitors. By taking such supplements she might become strong and excel, but it's not her efforts. So, I definitely would discourage her on this.