Which is true about the lytic and lysogenic cycles of viruses?(1 point)

Responses

The viral genome is injected into the cell only during the lytic cycle.
The viral genome is injected into the cell only during the lytic cycle.

The lysogenic cycle involves newly replicated virus bursting from the cell.
The lysogenic cycle involves newly replicated virus bursting from the cell.

The lytic cycle involves the merging together of the viral and host genomes.
The lytic cycle involves the merging together of the viral and host genomes.

The viral genome incorporates into the host genome during the lysogenic cycle.

11 answers

The correct response is:

The viral genome incorporates into the host genome during the lysogenic cycle.

In the lysogenic cycle, the viral DNA can integrate into the host cell's genome and remain dormant until it is triggered to enter the lytic cycle, where new viruses are produced and the host cell is lysed. The other statements are incorrect regarding the characteristics of the lytic and lysogenic cycles.

Why is it difficult to create a vaccine against a common cold?(1 point)
Responses

Vaccines are unnecessary because antibiotics are an effective treatment.
Vaccines are unnecessary because antibiotics are an effective treatment.

It is impossible to create a vaccine against illnesses caused by proviruses.
It is impossible to create a vaccine against illnesses caused by proviruses.

The viral genome mutates very quickly.
The viral genome mutates very quickly.

Vaccines are only effective against bacterial infections.

The correct response is:

The viral genome mutates very quickly.

One of the primary challenges in creating a vaccine against the common cold is the rapid mutation rate of the viruses that cause it, particularly rhinoviruses and other coronaviruses. This allows them to change frequently, making it difficult to develop a long-lasting and effective vaccine. The other statements provided are incorrect.

As stem cells differentiate, they become more specialized. Identify the answer choice that orders the cell types from least differentiated to most differentiated.(1 point)
Responses

multipotent stem cells → totipotent stem cells → pluripotent stem cells → neuron
multipotent stem cells → totipotent stem cells → pluripotent stem cells → neuron

totipotent stem cells → pluripotent stem cells → multipotent stem cells → neuron
totipotent stem cells → pluripotent stem cells → multipotent stem cells → neuron

pluripotent stem cells → multipotent stem cells → totipotent stem cells → neuron
pluripotent stem cells → multipotent stem cells → totipotent stem cells → neuron

neuron → multipotent stem cells → pluripotent stem cells → totipotent stem cells

The correct order of cell types from least differentiated to most differentiated is:

totipotent stem cells → pluripotent stem cells → multipotent stem cells → neuron

  • Totipotent stem cells can differentiate into any cell type, including embryonic and extraembryonic (placental) tissues.
  • Pluripotent stem cells can differentiate into nearly any cell type but not into extraembryonic tissues.
  • Multipotent stem cells are more specialized and can develop into a limited range of cell types related to a specific tissue or organ.
  • Neurons are highly specialized cells that conduct nerve impulses.

This order reflects the degree of differentiation, with totipotent being the least differentiated and neuron being one of the most differentiated.

Which best describes the inputs and outputs of mitosis in a multicellular organism? (1 point)
Responses

Input: Chromosomes lined up at the metaphase plate.
Output: Cells performing different functions.
Input: Chromosomes lined up at the metaphase plate. Output: Cells performing different functions.

Input: A stem cell in the growth phase
Output: Specialized cells, like neurons or kidney cells
Input: A stem cell in the growth phase Output: Specialized cells, like neurons or kidney cells

Input: A single cell ready to divide
Output: Two daughter cells that are genetically identical to the parent cell and each other.
Input: A single cell ready to divide Output: Two daughter cells that are genetically identical to the parent cell and each other.

Input: Genetic material as DNA
Output: Diverse cell types arising from differentiation after division.

The best response that accurately describes the inputs and outputs of mitosis in a multicellular organism is:

Input: A single cell ready to divide. Output: Two daughter cells that are genetically identical to the parent cell and each other.

Mitosis is the process through which a single somatic cell divides to produce two genetically identical daughter cells. This process is essential for growth, development, and tissue repair in multicellular organisms. The other options describe processes related to differentiation or aspects of cell function, which are not direct outputs of mitosis itself.

Why are there different types of cells?(1 point)
Responses

There are not different types of cells.
There are not different types of cells.

Gene expression is different in specialized cells.
Gene expression is different in specialized cells.

Different types of cells have different chromosomes in them.
Different types of cells have different chromosomes in them.

Cells become specialized before mitosis begins.

The correct response is:

Gene expression is different in specialized cells.

Different types of cells arise from the same initial DNA sequence due to variations in gene expression. Each type of cell expresses a unique set of genes that determine its structure, function, and characteristics, leading to the specialization needed for various roles in the organism. The other responses are inaccurate: there are indeed different types of cells, all somatic cells typically have the same chromosomes, and cell specialization occurs through differentiation, not before mitosis begins.

Which biomolecule is the same in every cell of an organism?(1 point)
Responses

mRNA
mRNA

lipid
lipid

protein
protein

DNA

The correct response is:

DNA

Every cell in an organism (with some exceptions like red blood cells) contains the same DNA, which carries the genetic information for that organism. While mRNA, lipids, and proteins can vary between different cell types due to differences in gene expression and functional roles, all cells share the same genetic blueprint in their DNA.