Can a catalyst be used over and over again?

Which statement summarizes the main purpose of photosynthesis?

An embryo is A a plant in its earliest stages of development B an animal in its earliest stages of development a bacteria in its earliest stages of development a plant or animal in its earliest stages of development

When you rub your hands together on a cold day, you use friction to convert A. Mechanical energy into thermal energy B. Thermal energy into nuclear energy C. Nuclear energy into electrical energy D. Electrical energy into electromagnetic energy

Tall land plants have requirements different from those of aquatic plants. which of these must the tall land plants have that aquatic plants do not need?

Sometimes, a person is born with one or more extra chromosomes in each cell. This usually results in abnormalities because the affected person has (1) a reduced number of genes in cell nuclei (2) fewer cell mutations than a person with a normal

B) humans and chimpanzees have very similar dna. what does this say about these two species

In a deciduous forest ecosystem which of these organisms would be a decomposer

How are viruses able to move between species?

Which of the following constructive forces was most powerful in the formation of the Appalachian Mountains? A. Crustal deformation due to two tectonic plates moving apart B. Crustal deformation due to two tectonic plates moving together C.

An antibiotic-resistant allele confers a fitness cost. What would you predict about the growth of the bacteria with the resistant allele compared to the growth of bacteria without the sensitive allele in the presence or absence of antibiotics?