Answer:
According to a mind-bending new theory, a black hole is actually a tunnel between universes—a type of wormhole. The matter the black hole attracts doesn't collapse into a single point, as has been predicted, but rather gushes out a "white hole" at the other end of the black one, the theory goes.
Answer:
The correct answer is - option B. They are small because they lack a nucleus.
Explanation:
Red blood cells or erythrocytes are specialized cell that produce in bone marrow and have specific role such as carrying oxygen from lungs to deliver it to the various organs and carry out carbon dioxide.
In mammals these cells lack cell organelles such as nucleus and mitochondria, a major factor that determined its smaller size. The size of RBC are move through narrow vessels throughout a organism because of its specific size and shape that provide it space for hemoglobin and allow to be flexible and bend to move through narrow vessels.
Thus, the correct answer is : option B. They are small because they lack a nucleus.
d. Sea Cucumber
Sea cucumbers are filter feeder. Sea cucumbers often find places that have strong currents to find food.