Answer:
The correct answer will be option-C
Explanation:
The rhythm of the heartbeat is controlled by the pacemaker of the heart called the sino-atrial node.
The SA node generates action potentials which trigger the contraction and relaxation of the atrium and ventricles. The membrane potential generation initiates by the depolarization of the cell membrane when the L type of Ca⁺² ions opens up and calcium ions enter the cell.
This depolarizes the cell until the potential threshold is reached which lies between the -40 and -30 mV.
Thus, Option-C is the correct answer.
The correct answer is B combustion.
Lavoisier’s oxygen theory of combustion was one of his most notable contribution to science and earned him the title of the “father of modern chemistry”. He recognized the combustible property of oxygen and that phosphorus and other metallic elements increased in terms of weight when burned.
Answer:
It depends on the structure of labeled A.
Explanation:
If the diagram shows the structure of flower, so we can say that it has the ability to attract insects and other animals. If the diagram shows the structure of an insect such as bees so we can say that it can moves the pollen to the ovaries. If the diagram indicates the structure of pistil which is a female part of the flower so we choose that it catches the pollen and if the diagram represents the structure of anther which is a female part so we choose that it produces pollen.
Answer: meiosis creates new combinations of genetic material in each of the four daughter cells. These new combinations result from the exchange of DNA between paired chromosomes. Such exchange means that the gametes produced through meiosis exhibit an amazing range of genetic variation.
Explanation:
