The ice has less density than liquid water, so it floats on the water surface. Therefore during the winter all the lakes and rivers are frozen only at a top. Deeper layers of water are cold, but still liquid and it allows fish and other organisms to survive. Moreover, the ice cover provides temperature isolation so liquid water beneath the ice has more or less constant temperature (around 4 dgr Celsius)
Answer
Commensal bacteria stimulate the immune system of the host to enhance defense mechanisms that block pathogen entrance and colonization. Moreover, by creating antimicrobial properties and signals & fighting with other bacteria for food and attachment sites, such bacteria might effectively limit the spread of respiratory infections. In healthy animals, the majority of commensal bacteria live inside the intestine's lumen, although some are also found in immediate contact with the intestinal epithelium. New studies have shown that commensal bacteria may live in stable stomach lymphoid tissues. But every once in a while, especially when they travel to other areas and leave their natural habitat, these commensal bacteria might cause illness. In both old and very and also in young persons, it can spread throughout the rest of the body, causing pneumonia, infection, and meningitis.
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Charles Darwin was B. A Naturalist on the Beagle voyage to South America. A naturalist observes and collects plant, animal, rock, and fossil specimens.
Answer:
Vision anthropology.
Explanation:
Anthropology may be defined as the study of the human and society of the present and past situation. Different fields of anthropology are vision anthropology, social anthropology and cultural anthropology.
Visual anthropology mainly deals with the study based on the photographic or films. This mainly involves the mass media to study any human relationship. The study become more effective by the visual presentation and making the things real.
Thus, the answer is visual anthropology.
the letter B. that is the answer
