Nina gets a new baby turtle from a friend, and is told to feed it worms. For the first few months, the turtle seemed to grow well. But as time passed, the turtle's shell appeared soft and fragile. Someone suggested that the turtle might not be getting enough calcium in its diet. If this is true for this turtle, dietary calcium is:. A. A limiting factor
B. An environmental condition
C. A habitat condition
D. A natural environmental stressor

Which of the following structures is not found in both plant and animal cells? a) chloroplast b) cytoskeleton c) ribosomes d) mitochondria

3points hurry! what is the relationship between biotechnology, sharkskin, and disease resistance? bioengineers have developed an artificial sharkskin that does not allow resistant bacteria to grow on it. disease-causing microbes have been genetically modified to keep them from infecting the skins of sharks. scientists have created a device that can be attached to the skins of sharks that dramatically increases their abilities to resist disease. sharkskin produces many chemicals that can be collected and used to create antibiotics.

The law of thermodynamics states that energy can't be created or destroyed. to natural sources of energy on earth are the