By 40-60 years after farm fields had been abandoned, the amount of herbaceous plants decreased. Give one reason why the amount of herbaceous plants decreased as the amount of trees increased.

Explanation:

Herbaceous plant are plants that lack woody stem, they include mostly annual crop and perennial crop.

The reduction in the population of herbaceous plant over the years is due to competition. The competition intensity is usually high due to limited supply of resource and the woody plant out compete the herbaceous plants leading to a gradual decline in the population.

Competition intensity is usually high during dry season when herbaceous biomass and soil water content were at the lowest level at this time the herbaceous plant finds it difficult to thrive well with the limited resource while the woody plant utilizes the little resource and keeps on thriving. All this reduce herbaceous population after several years of the field been abandoned.

advantage of using stem cells in medical research:

1.       it provides medical benefits in the fields of therapeutic cloning and regenerative medicine.

2. it provides great potential for discovering treatments and cures to a variety of diseases including parkinson disease, spinal cord injuries, diabetes, alzheimer’s disease and many more.

3. limbs and organ could be grown in lab from stem cells and then used in transplant or treat illness.

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.