Answer:
respiratory and excretory systems are among the two vital systems in our body which work in order to maintain our health or keep our body fit
Explanation:
Respiratory systems comprises of organs like lungs to inhale oxygen and exhale carbon dioxide out of our body. The oxygen is then mixed with blood by the heart and reaches different parts of our body.
Excretory system is responsible for excreting or expelling the waste out of our body to keep our body free from toxins and harmful chemicals.
excretory system works with respiratory system to get rid of water vapors and carbon dioxide in the human body.
Answer:
1. Physical models: smaller and simpler representations of the thing being studied. Eg. A globe or a map is a physical model of a portion or all of Earth.
2. Conceptual models: ties together many ideas to explain a phenomenon or event.
3. Mathematical models: sets of equations that take into account many factors to represent a phenomenon. Mathematical models are often done on computers.
4. Mental models: personal and internal representations of external reality that people use to interact with the world around them. They are constructed by individuals based on their unique life experiences, perceptions, and understandings of the world.
The chromosomes in the sex cells would be half the chromosomes in the body cells; so since each body cell has 40 <span>chromosomes and half of that is 20, there's your answer. It's B. 20</span>
Answer:
The answer is C. Nonpolar ends of phospholipids are exposed to watee inside and outside the cell
Answer: A protein domain is a region of the protein's polypeptide chain that is self-stabilizing and that folds
independently from the rest. Each domain forms a compact folded three-dimensional structure. Many proteins consist of several domains.
One domain may appear in a variety of different proteins. Molecular evolution uses domains as building blocks and these may be recombined in different arrangements to create proteins with different functions.
In general, domains vary in length from between about 50 amino acids up to 250 amino acids in length.
The shortest domains, such as zinc fingers, are stabilized by metal ions or disulfide bridges. Domains often form functional units, such as the calcium binding EF-hand domain of calmodulin.
Because they are independently stable, domains can be "swapped" by genetic engineering between one protein and another to make chimeric proteins.
