This is gravity.
Gravity is a force that is exerted on all objects on earth. The greater the mass, the greater the force of gravity is on an object.
Answer:
the cell wall
Explanation:
cell membrane is not rough and it doesn't support or protect the cell.
cytoplasm is the inner environment of the cell that includes organelles and nutritions. it's not rough and doesn't support or protect the cell.
Diverging plate boundaries, earthquakes occur as the plates pull away from each other. Volcanoes also form as magma rises upward from the underlying mantle along the gap between the two plates. We almost never see these volcanoes, because most of them are located on the sea floor.
Answer:
A nerve impulse from one neuron affects the activity of a neighboring neuron at a point of interaction called the: SYNAPSE
Explanation:
A NEURON(or nerve cell) has 3 parts:
1. The dendrites(multiple)
2. The axon
3. The cell body
A SYNAPSE is an area where the dendrites of one neuron communicates with the axon of another neuron.
At the synapse, nerve impulses are transmitted from one neuron to the other. This is possible through substances called NEUROTRANSMITTERS. There is no direct contact between the axon of one neuron and dendrites of another neuron.
Answer:
B) The "lub-dub" sound originates from blood turbulence through the heart.
Explanation:
The systole and diastole in the heart produce the lub and dub sound in the heart.
The systole represents the contraction of both left and right ventricles and pumps the blood to the body and the right ventricle to the lungs. This involves the opening and closing of the valves. The closing of the atrioventricular valves produces lub sound.
At the end of the systole or ventricular contraction or when the blood has been pumped to the aorta and the pulmonary valves then the semilunar valves present in the aorta and pulmonary closes. This produces a sound dub.
Therefore,lub dub is associated with the physical contraction of the heart but not the turbulence of the blood.
Thus, the selected option is the correct answer.
