Answer: "To move substances against a concentration or electrochemical gradient, a cell must use energy. Active transport mechanisms do just this, expending energy (often in the form of ATP) to maintain the right concentrations of ions and molecules in living cells."
Answer:
1) Skull and Vertebral column
2) Meninges
3) Cerebrospinal fluid.
Explanation:
Central Nervous system:
CNS is the abbreviation of Central Nervous system. CNS controls the whole body functions so it is the most important component of the body. CNS consist of two parts 1) Brain and 2) Spinal cord
Both of these organs are very important and hence need to be protected. Nature provided these organs with certain protective mechanisms these includes
1) Skull and Vertebral column:
Skull is present around brain and vertebral column is present around spinal cord. These structure provides mechanical support to soft parts of CNS.
2) Meninges:
These are the membranes that provide antiseptic environment to the brain and hence protect it from microbes and other harmful substances.
3) Cerebrospinal fluid:
This fluid is present inside meninges which nourishes the brain and protect it from mechanical stresses.
Answer:
They are the species which are found only in a particular area. They can be a plant, animal or microorganism. They are at great danger of becoming extinct due to the following reasons: - As they are restricted to a particular area so loss of their habitat is the major reason which could lead to extinction.
Explanation:
Answer: During mitosis a eukaryotic cell undergoes a carefully coordinated nuclear division that results in the formation of two genetically identical daughter cells.
Explanation:
Answer:
a wave is -a continuous and repeating disturbance of a medium- that carries-energy-from one place to another
Explanation: