A Human Biology Quiz Questions And Answers

Explanation
Benign tumors are non-cancerous growths that remain localized and do not spread to other parts of the body. They are usually slow-growing and have well-defined borders. Malignant tumors, on the other hand, are cancerous and have the ability to invade nearby tissues and spread to other parts of the body through the bloodstream or lymphatic system. They are typically fast-growing and can metastasize, making them more dangerous and difficult to treat compared to benign tumors.

Explanation
Metastasis is the process where cells detach from the primary tumor and spread to other parts of the body, forming secondary tumors. This is a crucial step in cancer progression and can occur through various mechanisms such as bloodstream or lymphatic system. Metastasis allows cancer to spread and invade distant organs or tissues, leading to the development of multiple tumors throughout the body.

Explanation
The correct answer is "proto-oncogens". Proto-oncogenes are genes that regulate cell division and prevent excessive cell proliferation. When proto-oncogenes mutate or become overactive, they can transform into oncogenes, which promote uncontrolled cell growth and can lead to cancer. The term "protooncogens" and "proto oncogens" are variations of the correct term "proto-oncogens".

Explanation
A mutation refers to a change that occurs in DNA. This change can lead to uncontrolled cell division.

Explanation
Cells contain genes called tumor suppressor genes, which code for proteins that stop the cell cycle. These proteins play a crucial role in preventing the formation and growth of tumors by inhibiting cell division and promoting cell death, a process known as apoptosis. When a cell's DNA is mutated, tumor suppressor genes are activated, leading to apoptosis in order to eliminate the damaged cell and prevent the proliferation of abnormal cells.