Answer:
have curved protofilaments at their plus ends
Explanation:
Microtubules are polymers of tubulin proteins that function as the cytoskeleton of eukaryotic cells. Microtubules are dynamic structures that can grow and shrink at a rapid rate. During this process, tubulin subunits can associate and dissociate at the plus end of the protofilament. Tubulin subunits bind to two GTP molecules, one of which is hydrolyzed to GDP after assembly. When microtubules are unstable, protofilaments curl outwards because GDP-bound tubulin has a weak affinity (thereby curving it) and disassemble. The dynamic stability of microtubules is regulated by a feedback loop: when microtubules shrink, free tubulin concentration increases and microtubules start to grow. As microtubules grow, free tubulin concentration decreases and the rate of GTP-tubulin addition also decreases.
The 4 properties given are physical properties, therefore the ones I'll list are also physical properties of sodium chloride.
These properties may include:
It is white in color
It is hard
It is brittle
It conducts electricity in molten or aqueous state
Salivary Glands: The salivary glands produce saliva and excrete amylase. Saliva helps lubricate the mouth and oropharynx. Saliva aids in the easy formation of a bolus, making it easier to swallow. Amylase aids in the break down of carbohydrates. The mouth is where the digestion of carbohydrates begins.
Gallbladder: The function of the gallbladder is to store and concentrate bile. Bile helps emulsify fats and neutralize acids.
Liver: The liver has many functions:
*produce bile
*detoxifies blood
*stores some vitamins and iron
* converts excess glucose to glycogen for storage
*converts ammonia to urea
*destroys old red blood cells, excretes bilirubin
*produces cholesterol
*produces certain proteins for plasma
*regulation of blood levels amino acids
*synthesizes albumin and clotting factors
Pancreas: The pancreas has two functions (exocrine and endocrine). The pancreas produces enzymes to breakdown proteins, lipids, carbohydrates, and nucleic acids (exocrine). The pancreas secretes the hormones insulin to lowers blood sugar and glucagon to raise blood sugar (endocrine).
Answer:
Breathing rate increases to provide the body (exercising muscles) with oxygen at a higher rate. Heart rate increases to deliver the oxygen (and glucose) to the respiring muscles more efficiently
