Answer:
C. Sprout every year, year after year
Explanation:
The perennial plants are the plants that live for more then two years, thous some may argue that they are plants that live more then three years. Whichever the case, they are not short-lived plants, but are capable of surviving for numerous years, unlike the annuals and biennials. Theoretically, the shrubs and trees would fall into this category, but they are classified separately, and this term is not used for them, but for smaller plants that do not have or have very little woody parts. These plants tend to sprout every year, and even though they seemingly die in the autumn, their roots are alive, and they emerge and grow again in the spring, sprouting again. That process repeats itself for numerous years.
<u>Answer</u>:- Active transport
<u>Explanation</u>:-
There are two types of membrane transports
1. Passive transport - this type of transport occurs without the input of any energy and the molecules move along the concentration gradients that is from <em>high concetration to low concentration.</em>
2. Active transport- this type of transport takes place to move the molecules against the concentration gradient that is from <em>low concentration to high concentration.</em>
<em>The active transport is of two types:</em>
1. <em>Primary active transport-</em> in this type of transport <em>ATP</em> is used as an energy source to move the substances against the concentration gradient.
2.<em>Secondary active transport</em> - in this type of transport the gradient formed by the active transport is utilized and it involves the movement of 2 substances at a time aross the membrane. That is the movement of one molecule is coupled to another.
- The membrane proteins that are associated with active transport are called as <em>carrier proteins</em>. These proteins have a binding site for the molecules that they transport. Once they bind to the specific molecules, a conformation change is induced and this leads to the transport of the molecule across the membrane.
So, the <em>active transport is basically responsible for utilizing the energy from ATP and carrier proteins to move the substances across the membrane against their concentration gradient i.e. from low concentration to high concentration.</em>
- The environment needs to change in order to natural selection to occur.
Reason:
Because, Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.
2. Population has some genetic variations.
Reason:
Genetic variation is essential for natural selection because natural selection can only increase or decrease frequency of alleles that already exist in the population. Genetic variation is caused by:
mutation and random mating between organisms
3. Nature select organism with specific traits to survive and reproduce.
Reason:
According to Charles Darwin's theory of evolution by natural selection, organisms that possess heritable traits that enable them to better adapt to their environment compared with other members of their species will be more likely to survive, reproduce, and pass more of their genes on to the next generation.
