Well the <span>blood returns from the cardiac tissues to the right atrium because
the blood goes through the tricuspid</span> valve and into the right ventricle then the right ventricle makes the blood go to the lungs and thats where the oxygen is at then the blood goes through organs and tissues then gets to the heart through the veins and a vein named the vena cave has the blood return to the right atrium.
Answer:
Insulin is a protein hormone which binds to the membrane receptor where as steroid hormones bind to the intracellular receptors.
Explanation:
Hormones can be divided into two groups based on their binding with receptor. Some hormones are water soluble like protein or peptide hormone (example is insulin) and catecholamines. These water soluble hormones cannot cross the plasma membrane of the target cell and thus bind to the membrane receptor. Binding to the membrane receptor leads to activation of intracellular enzymes which bring the physiological change. Steroid hormones in the other case can cross the plasma membrane and then bind to the intracellular receptors. The hormone receptor complex then either binds or activates specific portion of DNA to bring the physiological change.
Insulin is made by beta cells islets of Langerhans in the pancreas. It controls the levels of glucose. It is a small protein made of two polypeptides, one of 21 amino acids and the other of 30 amino acids. These two are called A chain and B chain and are linked together by disulphide bonds. The pro-hormone contains an extra stretch called C-peptide. During the maturation process the proinsulin looses the c-peptide to become mature insulin protein hormone. An american company called Eli Lilly, for the first time made recombinant human insulin.
Answer:
1. Mutation
2. Epigenetics
Explanation:
1. Mutation occurs when there is a change in an organism's DNA sequence as a result of mistakes in DNA replication or as a result of environmental factors like smoking. The mutation in a single organism can be passed on to other generations hence causing a genetic variation in the population, this obeys the Darwin's law that inherited traits (genetic) are passed on to other generations
2. Epigenetics are changes in gene expression that doesn't involve changes in the DNA sequences unlike mutation. This changes can be passed on to other generations and hence cause a variation in the population. This obeys the Lamarckian evolution that acquired traits are passed on to other generations.
A mutation is a change that occurs in our DNA sequence, either due to mistakes when the DNA is copied or as the result of environmental factors such as UV light and cigarette smoke.
U can look up the defeniton on google
Answer: D pharyngeal gill slits used for respiration
Explanation: