The four limitations are
1.It's often impossible to repeat trials on the same subjects.
2-Subjects may report an inaccurate medical history.
3-It can be difficult to control all possible variables.
4-It's impossible to come up with testable scientific questions for human subjects.
Research involving human beings is ultimately necessary for improvements in human health and welfare. Any results about healthy physiology, illness causes, treatment effectiveness, learning, or behavior must be verified by carefully controlled investigations involving human participants. Sadly, not all human research have been valid and beneficial. It is possible to harm people in the name of research. The most well-known instances happened in Nazi Germany. Investigations conducted after the war found several crimes, including experiments in which participants were submerged in extremely cold water to determine how long it would take them to pass away from hypothermia.
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Cell Differentiation<span> and Tissue. Within multicellular organisms, tissues are organized communities of </span>cells<span>that </span>work together<span> to carry out a specific function. The exact role of a tissue in an organism depends on what types of </span>cells<span> it contains.</span>
Answer:
The correct answer will be-
1. Chromosomes are made up of protein and nucleic acid.
2. Genes are located on chromosomes.
3. Chromosomes are found in the nucleus.
Explanation:
Watson and Crick are known for their findings on the structure of DNA in 1953. Their findings were motivated by the book called "What is Life?".
The book stated the concepts which were well accepted by the scientific communities that is the gene determines the trait which is located on the chromosomes proved by the experiments of Morgan.
The chromosomes are the condensed structure present in the nucleus was suggested by the Nageli in 1884. The chromosomes are composed of nucleic acid and protein was also proved and was well-accepted fact.
But the genes are made up of DNA was not well accepted which was suggested by the experiments of Avery in 1940s.
Thus, the selected options are the correct answer.
Answer:
1. Metaphase II - Chromosomes are lined up by spindle fibers.
2. Telophase II - Nuclear envelope forms around each set of DNA.
3. Anaphase II - Sister chromatids are pulled apart.
4. Prophase II - Centromeres move toward the poles of the cell
Explanation:
Answer:
Make up the skull and composed of the brain
Explanation: