Answer;
-PET scan
A PET scan uses radioactive markers in the blood to monitor blood flow and metabolic activity via x-ray
Explanation;
-A positron emission tomography (PET) scan is an imaging test that helps reveal how the tissues and organs are functioning. A PET scan uses a radioactive drug (tracer) to show this activity. This scan can sometimes detect disease before it shows up on other imaging tests.
-A PET scan is used to diagnose certain health conditions, to plan treatment, to find out how an existing condition is developing, and to see how effective a treatment is.
-In a PET scan, a machine detects radiation that is emitted by a radiotracer. A radiotracer consists of radioactive material that is tagged to a natural chemical, such as glucose.
A substance that has a specific shape and volume changes to a substance that has a specific volume is the statement that best describes this change in question. The correct option among all the options that are given in the question is the third option. I hope the answer helps you.
Answer:
Details about DNA are given in the explanation section. Hope it will be helpful for you.
Explanation:
DNA, or deoxyribonucleic acid, is the hereditary element in humans and almost all other organisms. Nearly every cell in a person’s body has the same type of DNA. Most DNA is found in the cell nucleus (nuclear DNA), but a small quantity of DNA can also be found in the mitochondria (mitochondrial DNA or mtDNA).
The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). Human DNA consists of about 3 billion bases, and more than 99 percent of those bases are the same type in all people.
DNA bases pair up with each other, A with T and C with G, to form units that are called base pairs. Each base is also attached to a sugar molecule and a phosphate molecule. A base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix.
A valuable feature of DNA is that it can replicate, or make copies of itself. Each strand of DNA in the double helix can serve as a pattern for duplicating the sequence of bases.
The levels of an environment to be organized are populations,species,community,and the ecosystem