The causitive agent of the cohesion-tension model of xylem transport is transpiration. During the process of transpiration, water vapor is lost from the stomata of the leaf. To replace this water, water from adjacent cells is withdrawn. The water molecules stick together due to cohesion and are transported upwards through the stem in the form of a stream.<span />
Answer:
<em>The correct option is A) Domesticated animals provided food and labor for cultivation.</em>
Explanation:
Domestication of animals benefited humans in numerous ways. The organisms were used for various purposes such as adequate supply of milk, meat, eggs etc. The animals were used for carrying materials from one place to another which made wok load easier for humans. Also, animals were used for cultivating processes such as ploughing which made cultivation process a lot easier for the mankind and as a result more food was produced.
Answer:
is one in which blood flows through two capillary beds before being sent back to the heart.
Explanation:
A portal system can be defined as a system of blood vessels having a capillary network at each end, meaning that the blood vessel starts and ends in capillaries, before finding its way back to the heart. The blood draining through the capillary bed flows via the larger vessel to supply the blood to the another structure's capillary bed.
Answer: Eukaryotic cells contain many membrane-enclosed, large, complex organelles in the cytoplasm whereas prokaryotic cells do not contain these membrane-bound organelles. Only eukaryotes possess a membrane-bound nucleus and membrane-bound organelles such as the mitochondria, golgi apparatus, lysosomes, peroxisomes.