1. <span>composed of cells with cell walls
2. </span><span>Vertebrates contain a backbone, while invertebrates do not.</span>
Answer:
Birds have remarkably specialized bones that are pneumatic, because they are full of air sacs that provide a continuous flow of breath throughout their bodies. In short, their lungs are essentially hooked up to their bones.
Answer:
Photosynthetic organisms (plants and/or phytoplankton) are at the bottom of the food chain.
Explanation:
The effect of such toxic chemicals to the body is that they stimulate uncontrolled cell division. Uncontrolled cell division or cells proliferation may lead to cancer. The unchecked cell growth results to mutations in genes that can cause cancer by accelerating cell division rates or inhibiting normal controls on the system, such as cell cycle arrest or programmed cell death.
Answer:
I and III only
Explanation:
Crop rotation is a farm practice that involves cultivating different species of crops on the same land at different seasons. In other words, the different crops are rotated. Crop rotation is done for various reasons including; improvement of soil fertility, pest and disease control etc.
In this case, a crop rotation of various grains and legumes would be an appropriate solution for the following problems:
- The nutrients in the soil on a farm are being depleted: Legumes are known to be rich in nitrogen and hence add nitrogen to the soil due to the nitrogen-fixing microbes in their roots. Hence, rotating between grains and legumes can help return the depleted nutrients (by grains) to the soil.
- A particular kind of pest is infesting the soil on a farm: Most pests are usually crop-specific, hence, planting only one type of crop can make that soil be infested with a particular kind of pest. However, rotating between crops such as grains and legumes can make a particular pests become scarce or less populated.
