Answer:
A reduction in habitat for arctic seals will results in reduced population of arctic seals in the pyramid of number with less energy to be derived in the pyramid of energy for the killer Wales since there's reduction of food the healed will obtain from arctic seals
Answer:
roots spread out underground like the branches of a tree as to get sufficient water and nutrients form the soil to transport to the other parts of the tree for its own growth , by spreading out roots tend to collect or suck the maximum nutrients
Answer:
D
Explanation: The tick is leaching off the human and the human doesn't get anything in return, which implies its parasitism.
Answer:
Option B, Conditioned stimulus
Explanation:
Conditioned stimulus is a stimulus that gets associated with a non neutral act .
Here, if salvation had taken place after smelling the food then it would have been an Unconditioned stimulus. But here "walking towards the front step" is an act that got associated with the salvation act which is a conditioned response .
Here a famous case of dog , food and bell can be seen for a better understanding.
a) Unconditioned stimulus - Smell of delicious food
Unconditioned response - salvation of dog
b) Now if a dog while feeding is made to hear some bell sound, then in near by future if he ever listens that bell sounds (Conditioned stimulus) he will associate it with food and ultimately will start salivating (Conditioned response)
Since lactose is absent, the repressor protein is blocking the genes and stopping transcription.
Option A.
<h3><u>Explanation:</u></h3>
Lac operon or lactose operon is the genetic mechanism of the cell to produce the enzyme digesting lactose by production of lactase enzymes. The bacterial cell has this mechanism of lac operon which controls the production of definite amount of lactase only in presence of lactose, to minimize the wastage of proteins.
In the lac operon, there are cap sites, promoter region, operator region, and the genes producing enzymes. In presence of lactose, protein produced from the promoter attaches with the lactose which acts as inducer and frees up the operator sites for RNA polymerase to act. But in absence of glucose, the operator site remains blocked, as in figure B, restricting the lactase production.