Organisms are classified as either prokaryotes or eukaryotes. Which of the following do the cells of all prokaryotes and eukaryotes contain?
{silence}Option A.{silence}
Cytoplasm and a membrane-enclosed nucleus
{silence}Option Be.{silence}
Genetic material and a nucleus that is not enclosed in a membrane
{silence}Option C.{silence}
A plasma membrane and a cell wall
{silence}Option D.{silence}
A plasma membrane and cytoplasm
The correct option is D. A plasma membrane and cytoplasm. Both prokaryotic and eukaryotic cells have a plasma membrane that separates the cell from its environment and cytoplasm, which is the gel-like substance inside the cell.
A student is studying microorganisms and recalls that one type of microorganism decomposes organic matter while another type fixes nitrogen from the atmosphere.
Which two types of microorganisms is the student describing?
Select TWO correct answers.
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The correct answers are:
1. Decomposers: These microorganisms break down and decompose organic matter, such as dead plants and animals. Examples include bacteria and fungi.
2. Nitrogen-fixing microorganisms: These microorganisms have the ability to convert atmospheric nitrogen into a usable form, such as ammonia or nitrates. Examples include certain bacteria and cyanobacteria.
During a severe windstorm on an isolated island, some pollen and seeds from conifers are carried high into the air in a cloud of dust. In which of these situations would the dust cloud containing the seeds and pollen be considered an agent for gene flow?
{silence}Option A.{silence}
The dust cloud is subjected to an extended period of ultraviolet radiation, causing a mutation in a gene of the conifer seeds.
{silence}Option Be.{silence}
The dust cloud settles, and a few of the conifer seeds return to the same environment.
{silence}Option C.{silence}
The dust cloud is subjected to electromagnetic radiation from the sun, causing the pollen to be unable to pollinate flowers.
{silence}Option D.{silence}
The dust cloud settles over a forest on a distant, isolated island and pollinates some conifer trees in that forest.
The correct option is D. The dust cloud settles over a forest on a distant, isolated island and pollinates some conifer trees in that forest.
Agent for gene flow refers to the movement of genes from one population to another. In this scenario, the dust cloud containing the seeds and pollen can act as a means of dispersal, carrying genetic material from one population of conifer trees to another population on a distant island. This can lead to gene flow between the two populations, potentially increasing genetic diversity and contributing to the overall genetic makeup of both populations.