Why is the controlled timing of gene expression crucial to an organism because it allows for which of the following?
The regulation of gene expression conserves energy and space. It would require a significant amount of energy for an organism to express every gene at all times, so it is more energy efficient to turn on the genes only when they are required.
How can a persons muscle cells have the same exact DNA sequences as their nerve cells even though they look and perform completely different?
How can person s muscle cells have the same exact DNA sequences as their nerve cells even though they look and perform completely different? The cells must mutate They have different DNA They must be heterozygotes Each cell type only activates the part of the genome that makes them that cell type.
Which statement is the most accurate all cells have the same genes?
What statement is correct? All cells have the same genes, but different genes are active in different cells.
What happens to e coli When lactose is not present?
What happens to E. coli when lactose is not present? The genes that produce the enzymes needed to break down lactose are not expressed.
What controls timing of gene expression?
Transcription factors (TFs) play an essential role in controlling how a cell will respond to a stimulus through the regulation of gene expression (1–3). The gene regulatory code, inscribed in the DNA of each gene, specifies how the production of each gene product will be controlled in space, time and magnitude.
What controls gene expression?
Specifically, gene expression is controlled on two levels. First, transcription is controlled by limiting the amount of mRNA that is produced from a particular gene. The second level of control is through post-transcriptional events that regulate the translation of mRNA into proteins.
What makes cells different from each other?
The cell types in a multicellular organism become different from one another because they synthesize and accumulate different sets of RNA and protein molecules. They generally do this without altering the sequence of their DNA.
Why do these cells have different phenotypes even though they are from the same individual?
These cells are different because they use the same set of genes differently. So even though each of our cells has the same 20,000 or so genes, each cell can select which ones it wants to “turn on” and which ones it wants to keep “turned off”.
Why are genes expressed differently in different cells?
A cell typically expresses only a fraction of its genes, and the different types of cells in multicellular organisms arise because different sets of genes are expressed. Moreover, cells can change the pattern of genes they express in response to changes in their environment, such as signals from other cells.
How do different cells have different functions?
The structural and functional characteristics of different types of cells are determined by the nature of the proteins present. Cells of various types have different functions because cell structure and function are closely related.
Which sugar is added in medium of E. coli?
lactose In E. coli, the lac operon is a group of three genes that code for the enzymes needed for lactose (a sugar) utilization by the cell. In an E. coli cell growing in a growth medium containing glucose as the only carbon source, the lac operon is "off" (not being transcribed).
When E. coli is inoculated in the medium containing both glucose and lactose which of the following Utilisation pattern will be observed?
The sequential utilization of these two sugars results in diauxic growth, where the cells first grow on glucose and then, following a short period of no growth, proceed to grow on lactose. This two-phase pattern of growth is also observed when E. coli is grown on mixtures of glucose and some other sugars2.
When cells express different genes What occurs?
Gene regulation makes cells different These different patterns of gene expression cause your various cell types to have different sets of proteins, making each cell type uniquely specialized to do its job. For example, one of the jobs of the liver is to remove toxic substances like alcohol from the bloodstream.
How do cells know which genes to express?
How do these cues help a cell “decide” what genes to express? Cells don't make decisions in the sense that you or I would. Instead, they have molecular pathways that convert information—such as the binding of a chemical signal to its receptor—into a change in gene expression.
Why do cells have different shapes and appearance?
Cells have different shapes because they do different things. Each cell type has its own role to play in helping our bodies to work properly, and their shapes help them carry out these roles effectively. The following cell types all have unusual shapes that are important for their function.
Why does the body need different types of cells give some examples of different cells?
Each type of cell in the human body is specially equipped for its role. Cells of the digestive system, for instance, are vastly different in structure and function from cells of the skeletal system. Cells of the body depend on each other to keep the body functioning as a unit.
Why do cells look different from each other?
Cells have different shapes because they do different things. Each cell type has its own role to play in helping our bodies to work properly, and their shapes help them carry out these roles effectively.
Why are cells different from each other?
The cell types in a multicellular organism become different from one another because they synthesize and accumulate different sets of RNA and protein molecules. They generally do this without altering the sequence of their DNA.
What do you think causes the four cells to appear and function differently from one another?
Transcription factors can turn on at different times during cell differentiation. As cells mature and go through different stages (arrows), transcription factors (colored balls) can act on gene expression and change the cell in different ways. This change affects the next generation of cells derived from that cell.
Why do cells not look the same?
Cells are the basic units of life and make up all living things. Millions of cells arrange themselves into tissues, which is what your skin is made of. Other living things, like bacteria, plants, and fungi are also made of cells. Since all cells have different jobs, they tend to look very different!
How do E. coli move?
Escherichia coli use long, whip-like structures called flagella to propel themselves. Motors in the cell's wall spin the flagella into bundles that rotate counter-clockwise, creating a twist that causes the bacterium to rotate clockwise, or towards the right when viewed from above.
How do you think E. coli will grow if given glucose and lactose as carbon source?
In an E. coli cell growing in a growth medium containing glucose as the only carbon source, the lac operon is "off" (not being transcribed). If we add lactose to the growth medium, the lac operon remains "off", with the cell continuing to utilize glucose.
Why does E. coli proliferates faster on glucose than lactose?
coli proliferates faster on glucose than lactose because: Lactose is taken up more slowly than glucose Lactose cannot be hydrolyzed by E.
Why does E. coli prefer glucose to lactose?
Lactose as an energy source E. coli prefers to use glucose as an energy source when both glucose and lactose are available. Lactose is an alternative energy source that can be used if glucose is absent.
Why do different cells perform different functions?
The structural and functional characteristics of different types of cells are determined by the nature of the proteins present. Cells of various types have different functions because cell structure and function are closely related.
Why do different cells have different functions?
The structural and functional characteristics of different types of cells are determined by the nature of the proteins present. Cells of various types have different functions because cell structure and function are closely related.
Why do cells have different organelles with different functions?
Together, the total area of a cell's internal membranes far exceeds that of its plasma membrane. Like the plasma membrane, organelle membranes function to keep the inside "in" and the outside "out." This partitioning permits different kinds of biochemical reactions to take place in different organelles.
In what ways do cells differ from each other?
Cells differ from each other by their functions/specialization and their organelles.
What are the differences between the two types of cells?
There are only two main types of cells: prokaryotic and eukaryotic. Prokaryotic cells lack a nucleus and other membrane-bound organelles. Eukaryotic cells have a nucleus and other membrane-bound organelles. This allows these cells to have complex functions.
Why do cells with different functions have different structures?
Cells of various types have different functions because cell structure and function are closely related. It is apparent that a cell that is very thin is not well suited for a protective function. Bone cells do not have an appropriate structure for nerve impulse conduction.