Answer:
The correct answer is - option B. They are small because they lack a nucleus.
Explanation:
Red blood cells or erythrocytes are specialized cell that produce in bone marrow and have specific role such as carrying oxygen from lungs to deliver it to the various organs and carry out carbon dioxide.
In mammals these cells lack cell organelles such as nucleus and mitochondria, a major factor that determined its smaller size. The size of RBC are move through narrow vessels throughout a organism because of its specific size and shape that provide it space for hemoglobin and allow to be flexible and bend to move through narrow vessels.
Thus, the correct answer is : option B. They are small because they lack a nucleus.
Pretty sure that the endocrine system is represented by the diagram
So the answer is endocrine
Secretin is a hormone produced in the intestines that promote the release of insulin from pancreatic islet cells.
Discussion about secretin:
- When fatty acids and acidic chyme are present, secretin is released. It performs a number of functions by attaching to secretin receptors, the majority of which are related to digestion and acid neutralization.
- In its principal function, secretin tells the pancreas to release bicarbonate ions into the pancreatic juice, raising the pH to between 8 and 8.3 in order to neutralize the acidic chyme. The pancreatic juice's digesting enzymes may function at their best as a result, safeguarding the duodenum's lining.
- Additionally, secretin controls the pyloric sphincter's tightness, gastrin release, HCl synthesis, and small intestine motility.
As a result, secretin also encourages the pancreas to produce more insulin in response to ingesting glucose.
Learn more about secretin here:
brainly.com/question/9225171
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Living organisms needs water to survive. fresh water also carries fresh nutrients.
Five to seven three to four
