Answer:
the correct sequence of the events happened during nerve impulse is (d): 2,1,4,3
Explanation:
Originally K+ ions remains inward the membranes while Na+ ions remains outward to maintain a resting potential of membrane.
Upon stimuli Sodium channels open on membrane and Na+ diffuses inward leading to the depolarization of membrane that is it becoming more positive due to Na+ and K+ ions.
To regain it polarized state or in repolarization state Potassium channels open and K+ begun to diffuse outward while Sodium channels gets closed and Na+ ions remains inside the membrane.
Potassium channels are not efficient as compared to Sodium Channels, so an excess amount of K+ion move outward so Hyperpolarization state achieved.
As the both ions are on the wrong side and will not be available for the next nerve impulse. Hence in Refractory period by the help of Na+/K+ pum, both ions move back to their original place and membrane achieve its resting membrane potential state.
I will answer this if I find the answer.
The answer is D, digestive.
Answer:
Explanation:
J. J. Thomson Electrons are scattered within the atom.
J.J. Thomson carried out experiment on the discharge tube in 1897 which led to the discovery of electrons as a subatomic particle. During this time, the whole atom was thought to be made of only electrons.
John Dalton Atoms are the smallest unit of an element.
John Dalton in 1808 proposed that atoms are the smallest indivisible particles of an element.
Ernest Rutherford Protons are at the center of an atom.
In 1911, Ernest Rutherford performed experiments using gold foil. He discovered that an atom is made up of a massive center made up of positively charged particles called protons.
Niels Bohr Electrons are in orbital levels.
Bohr in 1913 suggested that electrons are in specific spherical orbits around the central nucleus.
