Answer:
The lactose present prevents the production of lactase
Explanation:
This question is describing a set of genes in bacteria called LAC OPERON. Lac operon controls the production of lactase, which is the enzyme that digests lactose. However, this gene can be regulated at the transcription level i.e caused to be transcribed or not depending on certain factors.
According to the question, lac operon, which regulates the production of enzymes will be transcribed and subsequently translated i.e. turned on when there is a substrate (lactose) that the produced enzyme will work on. However, when there is no need of the lactase enzyme or there is absence of lactose (substrate), the lac operon gene is turned off.
Note that, the statement that "The presence of lactose prevents the production of lactase" is not correct.
It has warmed roughly 1.33°F.
I have searched everywhere, but I have not found the proposals of the question, but I will explain to you what is the endoplasmic reticulum so that you can answer it.
The endoplasmic reticulum is a eukaryotic organelle located in the cytoplasm.
The endoplasmic reticulum is a network of membrane tubules (often interconnected) scattered throughout the cytoplasm of eukaryotic cells. Its membrane, which alone represents more than half of the cellular membrane system, is in contact with the nuclear envelope.
The endoplasmic reticulum can be:
Granular (or rough) (RER) that is to say associated with ribosomes.
Smooth (SER).
The granular endoplasmic reticulum is the place of synthesis (in the associated ribosomes) of the proteins secreted outside the cell and of the proteins and lipids constituting the membranes of the cellular organelles. Golgi, lysosomes, mitochondria, nucleus, ribosomes, vesicles ...). It participates in the correct folding of the proteins that have just been synthesized.
The smooth endoplasmic reticulum participates in cellular metabolism, synthesizing lipids and storing calcium.
Answer:
In a chemical reaction, the atoms and molecules that interact with each other are called reactants. In a chemical reaction, the atoms and molecules produced by the reaction are called products.
Answer no 8:
The correct option is D) Antelopes with muscular legs are bale to outrun their predators better than antelopes with poor muscle tone. Thus they lived to reproduce.
Explanation:
Genetic variations in a population are the main reason that natural selection tends to occur. Natural selection favours those organisms which have better characteristics.The organisms with better traits are able to reproduce and pass on their characteristics to their offsprings.
Answer No 10:
The correct option is A) Phenotype directly influences the interaction of an organism with its environment.
Explanation:
The interactions between the phenotypic traits and the environment analyze whether a particular organism will be able to survive and pass on its characteristics to its offspring. Hence, the phenotype directly influences the interaction of an organism with its environment.
Answer No 9
The correct option is A) resistance to a virus
Explanation:
Mutations can be described as any changes which occur in the DNA of an organism. Mutations might be beneficial or harmful depending on the location where the mutation arises. Viruses are usually harmful for eukaryotes. Hence, the correct option is A.
Answer No 11:
The correct option is C) Giraffes with longer necks survived because they were better suited to the environment.
Explanation:
Natural selection tends to favour those organsims which are better suited to live in an environment. Those organisms with better characteristics are able to survive and pass on their traits to their offsprings.
The giraffes with longer necks were better adapted to live in the environment and hence were favoured by natural selection.
Answer No 12:
The correct option is D) selective breeding
Explanation:
Selective breeding can be described as a technique in which organisms with better characteristics are crossed, so that offsprings with better characteristics can be produced. Selective breeding is done by humans where as natural selection is done by the nature.