Blood vessels expand during hot weather and retract/ tighten in cold weather
Answer:
B. 100 percent yellow seeds
Explanation:
When a gene has two alleles and one allele is dominant over the other, the dominant allele is expressed in the heterozygous state and the expression of the recessive allele is masked. According to the given information, the allele for yellow seed color is dominant over the allele for the green seed color.
Let's assume that the allele "Y" gives yellow color to the seeds while the allele "y" is responsible for green seed color. A cross between two pure breeding yellow seeded (YY) and green seeded (yy) plants would produce all the yellow seeded progeny with genotype "Yy".
YY (Yellow) x yy (green) = Yy (yellow)
B. Global warming accelerates the greenhouse effect
<span>The living matter is composed of mainly six elements — carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur. These elements together constitute about 90% of the dry weight of the human body. Several other functionally important elements are also found in the cells. These include Ca, K, Na, CI, Mg, Fe, Cu, Co, I, Zn, F, Mo, and Se. Carbon is the most predominant and versatile element of life. It possesses a unique property to form an infinite number of compounds. This is attributed to the ability of carbon to form stable covalent bonds and C—C chains of unlimited length. It is estimated that about 90% of compounds found in living system invariably contain carbon.Life is composed of lifeless chemical molecules. A single cell of the bacterium, Escherichia coli contains about 6,000 different organic compounds. It is believed that man may contain about 100,000 different types of molecules although only a few of them have been characterized.</span>
