2. which of the following correctly identifies active transport? (1 point)
transport proteins move large molecules from areas of low concentration to areas of high concentration using cellular
energy
transport proteins move large molecules from areas of low concentration to areas of high concentration without the use of
cellular energy
small molecules move from areas of high concentration to areas of low concentration using cellular energy to enter a cell.
small molecules move from areas of low concentration to areas of high concentration without using cellular energy to enter a
cell.

D

Explanation: Passive= Small molecules and doesn't need energy

Active=Big molecules and does need energy

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.