How many times has winged flight evolved?

What lipids make up the cell membrane? how many layers does it hare? what are the functions of the cell membrane?

How is the skeleton similar to the frame of a house? both are made of calcium. both provide shape and support. both allow movement. both separate the structures into compartments.?

Remarkably, biologists are able to extract DNA from fragments of ancient Neanderthal bone and sequence Neanderthal DNA. Biologists are also able to come up with an accurate age of the remains. Some of these remains are as recent as 28,000 years old.

What is weather like in the deciduous forest? What are the five different zones, and how do they differ?

If a solution is considered to be basic, which of the following is true about the hydroxide ion concentration?

Which of the following is true about spring tides but is not true about neap tides? they must occur during a new moon in spring they occur during the moon's first quarter and third quarter phases they only occur during a full moon they can occur

Animal cells are bathed in an isotonic fluid, and plant and bacteria cells have a cell wall. What does this protect the cell membrane from?

Explain why latin is the basic for many scientific names

What is incomplete penetrance and what causes it? incomplete penetrance means the heterozygote has an intermediate phenotype between the two homozygous phenotypes because of interactions with environmental factors.

Support, protection of soft tissue, mineral storage, and blood formation are functions of what system?