Answer:
A. Lancelet
B. All chordates
Explanation:
A. Dorsal nerve chord is the only <u>unique feature</u> among all members of <u>phylum chordata</u> (mainly found in subphylum Vertebrata). In the given list, only lacelet is the Chordate whereas <u>snail belongs to phylum Mollusca</u>, <u>grasshopper belongs to Arthropda</u>, and <u>jellyfish belongs to Cnidaria</u>. Dorsal nerve cord runs along the length of organism's body.
B. <u>Gill slits</u> are <u>opening structures</u> to gills through which water passes from pharynx/throat to exterior. Their main purpose is to help filter the food particles available in surrounding water. Although they are typical for amphibians and fishes, chordates also possess gill slits at embryonic stages.
<span>The correct answer is b. Option a is incorrect because these models can demonstrate scientific theories, but they don't prove scientific theories (you would need experiments for that). Option c is incorrect because the models aren't always representing something abstract (i.e. DNA is very real, just very small). Option d is incorrect because they don't precisely mimic something in nature, but instead help us visualize something in nature that is difficult to see or comprehend.</span>
There is no attached table, so it could not be told precisely which of the four molecules is the DNA. But, it is known that DNA consists of deoxyribose, guanine, and phosphate.
The base unit of DNA is called a nucleotide. The nucleotide consists of a nucleobase (adenine - A, thymine - T, cytosine - C, and <u>guanine -G</u>), a monosaccharide <u>deoxyribose</u>, and a <u>phosphate </u>group. <span>By knowing this, it is easy to choose which molecule of those is the DNA.</span>
Answer:
Cellular respiration that proceeds in the absence of oxygen is anaerobic respiration. Cellular respiration that proceeds in the presence of oxygen is aerobic respiration.
