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:
D. Solid Ice Crystals
Explanation:
"Cirrus clouds are wispy, curly, or stringy. They are found high in the atmosphere—typically higher than 6,000 meters (20,000 feet)—and are usually made of ice crystals." -National Geographic
Answer:
the later stages are small and the tool materials are of better quality than the previous stages.
Explanation:
The stone scrapers and the choppers found at the site of Zhoukoudian points out the fact that Peking men devised several tools for various purposes and to accomplish different tasks. The stones and the bones used to make the tools used to be charred by using the fire. This also indicates that the Peking men had discovered the uses of fire and they used fire for various activities.