Flu<span>, </span>hepatitis A<span>, </span>hepatitis B<span>, </span>chickenpox<span>, </span>herpes zoster<span> (</span>shingles<span>), </span><span>cancer</span>
Gravity only depends upon the mass of an object.
Answer:
B: The shorter and more rounded the Appalachian Mountains are more than four times older than the taller and more jagged Rocky Mountains
Explanation:
- The Appalachian mountains form a system of mountains in eastern North America and are older than rocky mountains as they were formed 480 million years ago and are similar to those of the alps. They form a barrier to the east to the west.
- They extend to southeast Canada and form zones of 300 miles wide. They form the mountain ranges surrounding hills and the dissected plateaus forming at an elevation of 6,684 meters from the sea level. <u>Whereas the rocky mountains are younger and have an elevation of 4,401 meters.</u>
Answer: X and Y chromosomes.
Explanation:
<u>Chromosome that differs from other chromosomes (autosomes) in shape, size and behavior are called sex chromosome, allosome, heterochromosome or idiochromosome.</u> These sex chromosomes are typical mammalian allosomes and are sex-determining in species in which sex is determined by the XX-XY system. The presence of the XX allosomes determines female sex, while the XY allosomes are for male sex. These chromosomes contain different genes, where some are only on the X chromosome and others only on the Y chromosome, and a few are on both.
The size of the human X chromosome is 164 million bases and currently has 1,170 genes. It is composed of many repetitive DNA segments that do not code for any protein or their function is not known. Only 1.7% of the chromosome codes for functional proteins that are low in length compared to the average length of a human gene. It has a small number of genes known as housekeeping or constitutive -(responsible for the basic maintenance of the cell) and <u>most of the genes it contains are expressed in few tissues or are tissue-specific, which is especially true for those expressed in brain regions.</u> So, the X chromosome is larger and has more euchromatin regions than the <u>Y chromosome which only has genes that code for male sexual development</u>. Since females have two X chromosomes and males have only one, during development in females one of the X chromosomes is inactivated at random in each tissue to make a dosage compensation. Otherwise, females would be expressing twice as many genes as a male. And through inactivation and dosage compensation, both males and females will express the same number of genes.
