Answer:
In the adult heart, blood in the right chambers of the heart cannot enter the left chambers without passing through the lungs. (Ans. A)
Explanation:
In heart, heart muscle cells is responsible for the circulating the blood throughout the body. The heart contains four chambers, two upper called as atrium and two lower called as ventricle, 1 atrium and 1 ventricle present on both right and left sides of the heart.
Blood which is returning from other parts of the body and is no longer oxygen rich, enters from the top right chamber of the heart. Than this blood is pumped into the right vertical and through the pulmonary artery into the lungs for absorb more oxygen.This oxygen rich blood is then pumped into the top left chamber present in the heart, and then into the lower left chamber before being pumped out into the body from the aorta.
So, the answer is A.
Answer:
i would love to help you, but all of the answers are on the map...
Explanation:
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Answer:
Food webs either start with producers on<u><em> land </em></u>or with producers in <u><em>water</em></u>.
Explanation:
A food chain or a food web will always start with a producer and always end with a type of consumer. This is because producers are organisms which have the ability to make their own food. They are mostly plants or other producers like algae. Both aquatic and land food chains or food webs will start with a producer. An aquatic food web will generally start with a producer present in water. A land food web will mostly start with a producer from the land.
Answer:
B, that is, nitrogen-fixing bacteria in the soil convert nitrogen from the air to make nitrates.
Explanation:
As we know, Nitrogen cycle hold alot of importance in earth's geology because it moves the Nitrogen from soil to the atmosphere and then back to the biosphere fulfilling the Nitrogen needs of animals as well as plants.
Just like all other biogeochemical cycles, there are different stages of Nitrogen cycle through which an interchange of nitrogen between different reservoirs occur.
The Nitrogen present in the atmosphere is not usable for the animals and plants. However, there are some bacteria present in the soil called nitrogen-fixing bacteria that convert the atmospheric nitrogen to a usable form called nitrates. Plants are able to use these Nitrates and fulfill their nitrogen demands as nitrogen is the main component of the chlorophyll - molecule that makes photosynthesis possible.
Therefore B is the appropriate option.
Hope it help!
