CIE Biology Paper-4: Specimen Questions 18 - 19 of 120
Question number: 18
Write in Brief
What is difference between autotrophs and chemoautotrophs? Explain with examples.
Autotrophs are producers, which make their own food by the process of photosynthesis. These are also called as transducer because they convert radiant energy into chemical energy. Examples of autotrophs are –Green plants and some photosynthetic bacteria.
Chemoautotrophs are those producers, which make their food by some inorganic compounds. They use chemicals for self-nourishment. Example- cyanobacteria, Deep Sea thermal vents, where the main chemical present is sulfur. Nitrogen fixing bacteria are also the example of chemoautotrophs. They use nitrogen in soil.
Question number: 19
Write in Brief
Write short note about trachea cartilage
Trachea is made up of tracheal rings also known as tracheal cartilages. Cartilage is strong and flexible tissue. It support the trachea during respiration. There are generally sixteen to twenty individual cartilages present in C- shaped in the trachea, which varies from person to person. Each one is about one to two millimeters thick, with a depth of around four to five millimeters. One part of tracheal cartilages is peculiar tracheal cartilages, which are the first and last rings in the trachea. When a person grow old, the tracheal cartilages tend to stiffen. Their normal state is one of elasticity. Two or more cartilages often fuse together in the trachea, as part of the aging process.