<u>Answer</u>: Large collection of stars, gas, and dust held together by gravity.
<u>Explanation:</u>
- The name <em>galaxy</em> has been derived from the word <em>galaxies</em> which is a Greek word meaning milky.
- In simple words a galaxy is a collection of a large number of stars, however, to be more precise <em>a galaxy is a gravity-bound collection of stars, dust, gas, dark matter and stellar remnants. </em>
- There are different types of galaxies found in various shapes and size, some of the most common shapes being elliptical, irregular and spiral.
- An example is the milky way galaxy that contains our solar system.
Answer: How scientists define and measure population size, density, and distribution in ... In ecology, a population consists of all the organisms of a particular species ... some methods ecologists use to determine these values for populations in ... In the end, the data can be used to estimate the population size and population density
Answer:
The correct answer would be Atria push blood into the ventricles and Ventricles push blood out of the heart.
In humans, four chambered heart is present with two atria and two ventricles.
Deoxygenated blood from all over the body is passed into the right atrium through vena cava (superior and inferior).
Simultaneously, oxygenated blood from the lungs is passed into the left atrium of the heart with the help of pulmonary vein.
Both the atria contract at the same time to drain their blood into respective ventricles.
The ventricles undergo relaxation while receiving blood.
The valves present between the atria and ventricles (tricuspid and bicuspid valve) ensures that the blood flows in one way direction only. They shut down as the ventricles contract and produce the sound "lub".
The ventricles contract simultaneously to pump blood out of the heart. The right ventricle pumps deoxygenated blood into pulmonary artery which takes the blood to the lungs for oxygenation.
The left ventricle passes the oxygenated blood through aorta to all the parts of the body.
The pulmonary and aortic valves prevent the back flow of blood and shut at the same time which creates second sound called as "dub".
False
<h3>Explanation - </h3>
The process through which living organisms take oxygen inside the body is know as <em><u>Inhalation</u></em><em><u> </u></em>
Exhalation refers to the release of carbon dioxide from the body.
Where’s the diagram picture I won’t be able to answer if I’m not sure