Quiz In Biotechniques

Complementary RNA (cRNA) is not a type of RNA. The correct answer is cRNA.

A DNA microarray is a laboratory equipment used to compare the gene expression between two different cell types. It allows researchers to study the differences in gene expression on a large scale, by simultaneously analyzing thousands of genes in a single experiment. This is achieved by immobilizing small fragments of DNA on a solid surface and then hybridizing them with labeled cDNA or RNA samples. The resulting signal intensity indicates the level of gene expression, allowing researchers to identify genes that are differentially expressed between the two cell types.

A centrifuge is an instrument that spins at high speeds to separate materials based on their size or density. This is done by creating a centrifugal force that causes the heavier particles to move towards the outer edge of the spinning container, while the lighter particles remain closer to the center. This separation allows for the isolation of specific components or the removal of unwanted substances. Centrifuges are commonly used in various scientific and medical fields, such as biology, chemistry, and clinical laboratories, for tasks such as separating blood components, purifying DNA, or isolating specific cell types.

Cancer is a disease caused by genetic mutations that result in uncontrolled cell growth and division. These mutations can be inherited or acquired throughout a person's lifetime. The phrase "genes gone bad" refers to the fact that the normal regulation of cell growth and division is disrupted, leading to the formation of tumors. Down's Syndrome and Hemophilia are genetic disorders caused by specific gene mutations, but they do not involve uncontrolled cell growth like cancer does. Leukemia is a type of cancer that affects the blood and bone marrow.

All of the options mentioned in the question are indicators of a gene being turned on or expressed. When a gene is turned on, it is actively working and producing molecules of messenger RNA (mRNA). This process is known as gene expression. Therefore, if a gene is churning out molecules of mRNA, it means that the gene is turned on and being expressed. Therefore, the correct answer is "All of the above".

The term "gene expression" refers to the process by which information from a gene is used to create a functional product, such as a protein. It involves the transcription of DNA into RNA and the subsequent translation of RNA into protein. While DNA microarrays can be used to measure gene expression levels, "gene expression" itself is not a type of DNA microarray. DNA microarrays are specifically designed tools that allow scientists to study the expression of thousands of genes simultaneously. Therefore, "gene expression" is the correct answer as it is not a DNA microarray.

The correct answer is "multiple copies of a unique DNA sequence". In a microarray, each spot corresponds to a specific gene. The spots on the microarray are created by immobilizing multiple copies of a unique DNA sequence that represents that gene. This allows researchers to study the expression levels of different genes by measuring the binding of mRNA molecules from the sample to these spots. The presence of multiple copies of the DNA sequence ensures that the microarray is sensitive enough to detect the mRNA molecules accurately.

The reason why DNA doesn't stay in solution is because the strands of DNA are much longer than RNA molecules. This length difference causes DNA to be less soluble in solution compared to RNA.