Definite article is used before a noun (person place or thing) to indicate that the identity of the noun is known to the reader.
indefinite article is used before a noun that is general or when its identity is not known.
Answer:
My philosophy in life is to learn something everyday, to take care of my physical and mental health, and to enjoy life serving God.
Answer: The study, by Dr. Tim Brodribb and Dr. Taylor Field of the University of Tasmania and University of Tennessee, used plant physiology to reveal how flowering plants, including crops, were able to dominate land by evolving more efficient hydraulics, or 'leaf plumbing', to increase rates of photosynthesis.
Explanation: The reason for the success of this evolutionary step is that under relatively low atmospheric C02 conditions, like those existing at present, water transport efficiency and photosynthetic performance are tightly linked. Therefore adaptations that increase water transport will enhance maximum photosynthesis, exerting substantial evolutionary leverage over competing species.
The evolution of dense leaf venation in flowering plants, around 140-100 million years ago, was an event with profound significance for the continued evolution of flowering plants. This step provided a 'cretaceous productivity stimulus package' which reverberated across the biosphere and led to these plants playing the fundamental role in the biological and atmospheric functions of the earth.
Pond water contains a variety of plant and animal life. While some are visible to the plain eye, others require a microscope to observe them. For example, there's bacteria, protozoa, hydras, algae, and arthropods. You will have the opportunity to see a number of microorganisms from both the plant and animal kingdom.
B is not part of the cell theory; there are many types of cells that do not have cell walls, so the statement cannot even be generally true.