As the heart beats, it pumps blood through a system of blood vessels, called the circulatory system. The vessels are elastic, muscular tubes that carry blood to every part of the body.
Blood is essential. In addition to carrying oxygen from the lungs and nutrients to your body's tissues, it also takes the body's waste, including carbon dioxide, away from the tissues. This is necessary to sustain life and promote the health of all the body's tissues.
F. b and c only the Sun is closer to the horizon <span> the Sun’s light is spread and diluted more</span>
Elements pass from one organism to another and among parts of the biosphere through closed loops called biogeochemical cycles, which are powered by the flow of energy.
Answer: B - People with two copies of the mutated gene have sickle-cell anemia. People with one copy of the mutated gene have both healthy and misshapen red blood cells and are carriers of the disease.
Explanation:
Co-dominance is when both the alleles of a gene in a heterozygote show. In the case of sickle cell anemia (since it is a co-dominant trait) even if the person only has one sickle cell allele, symptoms of sickle cell will still show up in that person. That's why the person in this example has both misshapen and healthy red blood cells.
Answer:
D) It would contain less nitrogen.
Explanation:
In an investigation of the cycling of environmental gases, a student placed water and bromthymol blue in each of four test tubes as shown in the diagrams below. No additional items were placed in tube 1, a snail was placed in tube 2, an aquatic plant (elodea) was placed in tube 3, and both a snail and an elodea were placed in tube 4. The tubes were then stoppered and placed in bright light for 24 hours. The solution in tube 3 changes after 24 hours because it would contain less nitrogen.
The dfferent tubes are shown in the picture that I uploaded.