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.
Single circular piece of DNA
Answer: A. Mesopelagic zone
Explanation: This zone is referred to as the "middle zone" within oceanic waters. Not yet the deep zone, however past the top layer aka upper ocean.
Hope this helps ^^
Answer: The correct answer is choice D.
Explanation: We can see on the cladogram that these two are in the same branch and lead to the same common ancestor. These two happen to share the most recent common ancestor, however.
Animals that live in temperate woodlands, the Arctic, tundras, and other forest animals such as wolves,, bears, and chipmunks have large amounts of fur and store large amounts of body fur for hibernation purposes.