Where does mechanical and chemical breakdown start in the digestive system?

Biology

1 answer:

slamgirl [31]3 years ago

4 0

The answer is D.

Both mechanical and chemical digestion of food begin in the mouth.

Mechanical digestion involves physically breaking down food into smaller pieces. This happens in the mouth as the food is chewed. Adult humans have 32 specialized teeth which can tear, grind and chew different kinds of food.

Chemical digestion also begins in the mouth. It involves breaking down food into simpler nutrients that can be used by the cells. In the mouth, food is mixed with saliva. Saliva contains an enzyme called salivary amylase that begins the breakdown of carbohydrates. Salivary glands beneath and in back of the tongue secrete the saliva.

You might be interested in

Vascular tissue is important to a plant because it

stiv31 [10]

<span>Vascular plants are able to grow higher than other plants due to the rigidity of xylem cells, which support the plant.</span>

8 0

3 years ago

Omg i need the answer lol

galina1969 [7]

Answer:

Force is a measure of power. Velocity, on the other hand, is a quality an object has. Apply force to an object, and its velocity changes.

6 0

3 years ago

Studies reveal that ventilation drifts upward during constant-load submaximal exercise performed in a hot and humid environment.

Rina8888 [55]

<span>The answer would be; a significant increase in blood temperature.

The muscle contraction from exercise will produce heat that will increase the body temperature. In a hot and humid condition, this will make the body temperature hard to be lowered. The increase of blood temperature will influence the respiratory control center, makes the respiration drift upward.</span>

6 0

3 years ago

If organisms A, B, and C belong to the same class but to different orders and if organisms D, E, and F belong to the same order

zalisa [80]

Answer:

Any combination of D, E and F

Explanation:

Since A, B, and C belong to different orders, and D, E and F belong to the same order, the latter are more closely related and thus are expected to show a greater degree of structural homology. They are closer to their common ancestor than A, B and C.

7 0

3 years ago

When 238u92 becomes , 234Th90 what type of decay has taken place?

ruslelena [56]

Answer: alpha

Explanation: Alpha particles are fast moving streams of positively charged particles that are shown to be Helium nuclei. They have a mass

number of 4 and an atomic number of 2 and a charge of +2. Alpha particles are represented as 4He2. When 238U92 becomes 234Th90, it emitted a helium nucleus 4He2. The equation for the decay is 238U92 ---> 234Th90 + 4He2.

6 0

3 years ago