The Cambrian explosion was a period at the Pre-Cambrian boundary of the geologic time scale at 542 Ma. At this boundary, the fossil record shows that animals suddenly appeared in a dramatic radiation of life. A radiation is the relatively rapid development of new types of organisms that derive from a common ancestor. The Cambrian explosion is important because it marks the origination of all major animal groups called phyla.
Answer:
b. thick wall.
Explanation:
Endospore is a structure formed by some bacteria, that help them survive unfavourable conditions (e.g. lack of nutrients). This survival strategy of some bacteria (usually Gram+ bacteria) help them stay dormant for a while, until stressful conditions stop. A thick wall composed of many layers (exosporium, spore coat, spore cortex, core wall) of the endospore is what provides resistance to different stressful chemical and physical factors such as UV radiation, temperature, chemical damage etc.
Anaerobic respiration can be sustained for short periods of time because you aren’t using oxygen. We need oxygen in our body to work our muscles and pump our heart.
In meiosis? Tetrads maby? When two homologus chromosomes do crossing over they're called tetrads so..
The answer is the control group.
the group in an experiment that is not exposed to the tested variable is called the control group
