Answer:
Each organ system performs specific functions for the body, and each organ system is typically studied independently. However, the organ systems also work together to help the body maintain homeostasis.
For example, the cardiovascular, urinary, and lymphatic systems all help the body control water balance. The cardiovascular and lymphatic systems transport fluids throughout the body and help sense both solute and water levels and regulate pressure. If the water level gets too high, the urinary system produces more dilute urine (urine with a higher water content) to help eliminate the excess water. If the water level gets too low, more concentrated urine is produced so that water is conserved. The digestive system also plays a role with variable water absorption. Water can be lost through the integumentary and respiratory systems, but that loss is not directly involved in maintaining body fluids and is usually associated with other homeostatic mechanisms.
Similarly, the cardiovascular, integumentary, respiratory, and muscular systems work together to help the body maintain a stable internal temperature. If body temperature rises, blood vessels in the skin dilate, allowing more blood to flow near the skin’s surface. This allows heat to dissipate through the skin and into the surrounding air. The skin may also produce sweat if the body gets too hot; when the sweat evaporates, it helps to cool the body. Rapid breathing can also help the body eliminate excess heat. Together, these responses to increased body temperature explain why you sweat, pant, and become red in the face when you exercise hard. (Heavy breathing during exercise is also one way the body gets more oxygen to your muscles, and gets rid of the extra carbon dioxide produced by the muscles.)
Answer:
Explanation:
Why are layers of rocks related to each other?
Layering, or bedding, is the most obvious feature of sedimentary rocks. ... This Law of Superposition is fundamental to the interpretation of Earth history, because at any one location it indicates the relative ages of rock layers and the fossils in them. Layered rocks form when particles settle from water or air.
Answer:
A) A mutation in a single gene can result in a defective protein.
Explanation:
This hypothesis states that one gene codes for one protein-enzyme, so consequently, if mutation occurs in that gene, the enzyme will not work properly. This hypothesis was very important for the fundamental discoveries of molecular biology, but it is oversimplified meaning that relationship between genes and proteins is much more complex.
B - Because an active cell can only work if it has a 3-Dimension structure.
In the small intestine, cells contain microvilli, which are tiny hair-like projections that increase nutrient absorption. These projections increase the surface area of the small intestine allowing more area for nutrients to be absorbed.