Answer:
The correct answer is - 10³ seconds.
Explanation:
The nerve impulse is an electrical signal in which fluctuation in membrane potential occurs and forms an electrical signal that takes place that travels along the axon to the synapses.
Suppose a nerve impulse starts only when the first impulse ends according to the question so the one impulse last for the 10⁻³ second or 1 ms.
Thus, the nerve impulse fires per second will be equal to impulse generate in each second which is 1/10⁻³ = 10³.
Thus, the correct answer is - 10³ impulse per second or 1000 impulse per second.
Answer:
In a research there are two variables independent and dependent variable. independent variable is defined as the variable which is controlled and changed in a scientific experiment and evaluate the effects on the dependent variable while the variable which are tested and measured in experiment are called dependent variable.
When antibiotic is sprayed at one side of the petri dish, the bacterial growth on that side will eventually decrease in comparison to other side.
So, the independent variable in this experiment will be antibiotic because it is used to understand the growth of bacteria by decreasing their numbers and the dependent variable in this experiment will be bacteria as they vary according to the change in independent variable that is antibiotic.
Oparin-Haldane hypothesis. The Oparin-Haldane hypothesis is named after the two scientists; <span>Russian scientist Aleksandr Oparin and English scientist J. B. S. Haldane. The two scientists separately hypothesized that life began when some inorganic molecules were converted into organic molecules specifically amino acids by the help of energy came from a lightning struck.</span>
Answer:
<em>In the lungs, the blood receives oxygen then leaves through the pulmonary veins. It returns to the heart and enters the left </em><em>atrium</em><em>.</em>