Answer:
The moonlight we see on Earth is sunlight reflected off the Moon's grayish-white surface. The amount of Moon we see changes over the month — lunar phases — because the Moon orbits Earth and Earth orbits the Sun. ... During a lunar eclipse, Earth comes between the Sun and the Moon, blocking the sunlight falling on the Moon.
Explanation:
Answer:
Hypoxia or low levels of oxygen
Explanation:
One of the negative impacts of eutrophication and increased algal growth is a loss of available oxygen, known as hypoxia. These anoxic conditions can kill fish and other aquatic organisms such as amphibians.
Answer:
<em>Farmers are the ones who grow crops. These plants are eaten by animals and humans. The humans then feed on animals and so on. </em>
Explanation:
The chain of feeding occurs from one trophic level to another. The organism of higher trophic level feed on organism of lower trophic level. This process is called as food chain.
In the process of food chain, the flow of energy occurs. Nonetheless, just 10% of the consumed energy streams starting with one trophic level then onto the next as some of it is utilized for metabolic exercises.
Answer:
The correct order is dehydration, embed in wax, cut into sections, staining
Explanation:
There are certain proceedings needed to obtain stained sections of vegetable or animal tissues for their microscope observations.
These steps are:
- Obtention of the material: The tissue is cut to an adequate size.
- Fixation: When tissues are extracted from the organism, they suffer autolysis and putrefaction, so they need to be fixated in order to keep their cells in the best state possible. Fixation involves preserving the original morphological and molecular characteristics of the tissue. Fixation avoids autolysis, putrefaction, distortion, and retraction of cells and the tissue that could affect its volume or morphology.
- Dehydration. Once fixated, the fixator must be eliminated and the tissue is dehydrated by using a gradual series of solutions with alcohol in ascendant concentrations. Dehydration must be gradual to avoid tissue deformation.
- Inclusion. To obtain thin cuts that can be observed under the optic microscope, the tissues must be included in a consistent, firm substance, that might be either hydrophilic or hydrophobic. A hydrophobic medium is paraffin wax, that provides hardness and plasticity.
- Cut. The tissue included in wax must be cut in slides or sections thin enough to allow the diffusion and penetration of light. A microtome is used to perform these cuts. When using paraffine for tissue inclusion, the cuts are about 5 to 20 micrometers of thickness.
- Stain. Once the cuts are performed, paraffin wax must be eliminated. This can be done by using an organic solvent. Then the tissue must be stained. Hematoxylin and Eosin are the most common dyes. Animal tissues in general do not have any natural color, so they need to be stained to be observed.
Answer:
Photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds.
