Answer: The question is not complete as options are not complete , the remain part are;
A. 3.7 years, photosynthetic bacteria.
B. 3.7 years cyanobacteria.
The correct option is
3.7 billion years old, cyanobacteria and stromatolite.
Explanation:
This is because cyanobacteria is the oldest fossil to exist and they have been in existence for about 3. 7 billion years. These cyanobacteria photosynthesized because they have thread like chlorophyll filament, they produce food through the process of photosynthesis which is needed for their survival and they release oxygen as bye product.
Carbon dioxide from the yeast comes from a process called fermentation. Fermentation is a cellular respiration process in cells that happens when oxygen is not present. If oxygen is present, the process is called aerobic respiration.
Answer:
4. p.complement system c.saliva b.sneezing
False, I'd say. Mammals usually adapt based on environment. Now, I know predators are "apart" of the environment, but I don't think that'd be it. I'd bet more money on saying mammals evolve based on environment adaptation. Sorry if I didn't answer your question or if I didn't get my point across well.
Answer:Toothed whales do not make the long, low-frequency sounds known as the whale song. Instead they produce rapid bursts of high-frequency clicks and whistles. Single clicks are generally used for echolocation whereas collections of clicks and whistles are used for communication.