Answer:
Your heart changes its rate depending on the activity, so that it can carry blood to your muscles, and therefore it needs to beat stronger if you are performing some exercise, or not so strong if you are sleeping, for example.
Explanation:
Your heart is continuously beating to keep blood circulating throughout your body.
So, here it is why your heart changes its rate: Its rate changes depending on your activity level; it is lower while you are asleep and at rest and higher while you exercise to supply your muscles with enough freshly oxygenated blood to keep the functioning at a high level.
And how: depending on your activity level, your heart has to pump enough blood to your muscles. Blood carries needed oxygen and other nutrients. Muscles need more blood sugar than any other tissue especially when working hard. To supply your muscles with oxygen your heart needs to beat faster, and this builds up your heart muscles.
<span>Transversus abdominis is the abdominal muscle that can only compress the abdomen</span>
Answer:
The question to be asked an investigated when observing a structure under the microscope to determine whether it is living is if it has a nucleus if eukaryote or nucleoid if prokaryote.
Explanation:
The major organelle that must be present in all living cells is the nucleus or nucleoid and the protoplasm. The observation of the cell under the microscope will show the subcellular entity, nucleus/nucleoid, more pronounced than other organelles in the cell. The nucleus house the necessary information for the maintenance and reproduction, which is mainly the genetic information that dictates the translational protein products that are needed to build another aspect of the cells. Therefore, when such a tiny structure is placed under the light microscope under the view of oil immersion, the nucleus of the cell should be visible if it is a living structure.
Answer:
<u>3) Uncontrolled cell division occurred as a result of gene mutations</u>
<u />
Explanation:
Spontaneous modifications within the genome may occur during the process of cell division. When copies of the DNA inside the cell are made, these mutations cause errors; and can include small single nucleotide polymorphisms, and large scale additions or deletions across multiple genes.
Some, like somatic mutations, exist only inside vegetative (body) cells, that cannot be passed onto offspring. This is caused by several factors like
- UV radiation,
- chemical mutagens,
- infective agents
UV radiation damages strands of DNA, by causing dimers to form; here, consecutive nucleotide bases covalently bond instead of those on the complementary strand. This conformational change causes errors in DNA proofreading and repair mechanisms where bases are not well-incorporated into the strand- tumors (clumps of uncontrolled cell growth) may form, resulting in melanoma, a type of skin cancer.
