Question

Which sentence is correct? All cells have the same genes, but different genes are active in different cells. Lungs look different from the heart because the cells that make up these organs have different genes. All cells have the same genes, and all of a cell's genes are active at the same time. As cells and tissues differentiate, they lose some of their genes.

Answer 1

The correct sentence among the options provided is: All cells have the same genes, but different genes are active in different cells.

Step-by-step explanation:

The correct sentence is that all cells have the same genes, but different genes are active in different cells, which explains why different cells have various structures and functions due to differential gene expression.

This statement is in line with the biological concept of gene expression. In multicellular organisms, every cell has the same set of DNA and thus the same genes.

However, what makes cells different in their structure and function is which genes are actively being expressed. Differentiation of cells into various types like muscle, liver, or skin cells involves the activation of different sets of genes, which results in the production of different proteins that give a cell its unique characteristics. This is known as differential gene expression, dictating why for instance an eye cell is different from a liver cell, even though they have the same genetic material.

Unicellular organisms also regulate their gene activity, turning on or off genes to respond to environmental changes. However, the differences in the cells of multicellular organisms are a consequence of the specific sets of genes they express at certain times, based on the demands and function of each cell.

Answer 2

All cells have same genes, but different genes are active in different cells

Step-by-step explanation:

Most living organisms are made up of different kinds of cells specialize in performing various functions like nerve cells perform different functions than blood cells. But all the cells are composed of same set of genetic information.

Since biochemical function is found out mainly by some specific enzymes, different sets of genes must be turned on and off in the various cell types to perform different functions. This is how cells differentiate for different functional capabilities.