The two events that occur when gravity causes a nebula to collapse into itself are:
A. Nuclear fusion start.
B. A new star forms.
Explanation:
- Nebula are giant clouds of dust and gases.
- These clouds are considered as progenitors of stars and planets.
- The gravitational pull within these giant clouds result these large masses to collapse towards their centre.
- The gravitational collapse results in tremendous rise in temperature till a point where nuclear fusion begin .
- The stars are born out of such mechanism and act as a source of heat and light in universe.
Answer:
EKG is a test that measures the electrical activity of the heartbeat. With each beat, an electrical impulse (or “wave”) travels through the heart. This wave causes the muscle to squeeze and pump blood from the heart.
Answer:
response to stimuli / tropism
Explanation:
The plants and animals always respond to stimuli. It is an innate character of all living things. When a bright light falls on the eye, it closes immediately. This is responding to the stimuli. When someone touches the leaves of touch-me-not plants it closes its leaves due to the external stimuli.
The plants respond to the light. Because it does photosynthesis in the presence of light. Therefore, the leaves and branches of the plants always bend towards the light. This process is called phototropism.
Similarly, the roots of the plants move towards gravity under the ground. This is called geotropism.
Besides phototropism and geotropism, other types of stimuli are there - hydrotropism(response to the water), chemotropism(response to certain chemicals).
That's why the plants growing on the windowsill move towards outside where light comes.
The right answer is organelle G, which represents mitochondria.
Mitochondria is the place of cellular respiration. This is a set of reactions that convert glucose into the energy molecule, ATP. This process involves several steps, including the "Krebs Cycle", a set of metabolic reactions that takes place in the mitochondrial matrix. The enzyme that produces ATP is found in the inner membrane of the mitochondria. For these reasons, the mitochondria is often referred to as the cell's energy factory.
<span>The best way to avoid running aground
is to ensure that you have a good understanding of your environment. This can be
achieved by gaining familiarity with locations of shallow water and learning to
read a chart to determine one’s position and the level of water</span>
