Answer:
gills
Explanation: A fish without a jaw was the first vertebrate to evolve. These fish used filtration to capture their food and sucked water and debris from the sea through their mouths and then released the water and trash through their gills. Some features are as follows:
1. They have a notocorda that serves as support through the back of the fish.
2. Gill bags. These organs are responsible for filtering the oxygen in the water.
3. A pineal eye that is sensitive to light
4. A cartilaginous skeleton
Answer:
5. under aerobic conditions most of the pyruvate generated as a result of glycolysis is oxidized by the citric acid cycle rather than reduced to lactate.
Explanation:
The contraction of muscles occurs in the presence of Adenosine Triphosphate (ATP) because ATP supplies the muscles with the energy they require for contraction.
Muscles can undergo contraction Aerobically ( in the presence of oxygen) or Anaerobically ( in the absence of oxygen).
When a muscle is stimulated to contract aerobically, less lactic acid is formed than when it contracts anaerobically because under aerobic conditions most of the pyruvate generated as a result of glycolysis is oxidized by the citric acid cycle rather than reduced to lactate.
Answer:
Tropism can be called positive or negative. Positive tropism is movement or growth towards a stimulus, whereas negative tropism is the movement or growth away from a stimulus.
Explanation:
Answer:
Statement C is the only one that is necessarily true for exons 2 and 3. It is also true for exons 7 and 8. While statements A and B could be true, they don’thave to be. Because the protein sequence is the same in segments of the mRNA that correspond to exons 1 and 10, neither choice of alternative exons (2 versus 3, or 7 versus 8) can alter the reading frame. To maintain the normal reading frame—whatever that is—the alternative exons must have a number of nucleotides that when divided by 3 (the number of nucleotides in a codon) give the same remainder. Since the sequence of the a-tropomyosin gene is known, it is possible to check to see the actual state of affairs. Exons 2 and 3 both contain the same number of nucleotides, 126, which is divisible by 3 with no remainder.
Bacteria is important because this bacteria binds hydrogen molecules with the gaseous nitrogen to form ammonia in the soil. During assimilation, or when plants take up nitrates from the soil, bacteria aid in the process with the plants in making ammonia. Animal wastes is also a major place where bacteria thrives and produces ammonia. The process in which assimilation occurs in plants, and then bacteria converts the nitrates to ammonia is called ammonification. From the conversion of ammonia to nitrites, bacteria also aids in this process called nitrification. The nitrifying bacteria mostly present in soils, oxidize ammonia into nitrites, and from nitrites to nitrates.
Finally, the process of denitrification also has bacteria present to aid in converting nitrates back into a gaseous form of nitrogen in the atmosphere.
