Example 1:
Endoplasmic reticulum (ER) are like factories of cells. If we consider cell as a international clothing chain of companies, then ER are the ones which plan and design the clothing, sew those up, put additional buttons etc. on them, and then ship them on time. The workers (manual and automatic) do the whole procedure.
To understand it better in terms of cellular functions, ER create biomolecules essential for cells and the body as a whole. ribosomes are the workers which do the synthesis. With the help of ribosomes, ER makes the whole process of biomolecule synthesis, modification and delivery smooth, efficient and accurate.
Example 2:
Think of ER as Uber Eats. It provides you the catalogue of delicious food available and can be sent, then forwards your request to the restaurant, then sends a delivery person to wait and collect the order, and then orders the person to delivery food to the correct address on time.
Here, ribosomes would be the restaurants making the food.
**This is a simplification of the actual function of ER but I hope you get the gist. While talking about smooth and rough ER, the examples may change.
The half-life of carbon-14 is equal to 5730 years. The amount of substance with half-life h at any time t is equal to,
At = (Ao) x (1 - 0.5)^(t/h)
Substituting,
At/Ao = 0.67 = 0.5^(t/5730)
The value of t from the equation is 3310.6 years.
Answer:
https://study.com/academy/answer/what-joint-is-formed-between-the-ulna-and-radius.html
Answer:
C
Explanation:
It gives a cause and effect, basically it describes one event and explains how it led to another.
Natural selection is the process by which individuals with characteristics that are advantageous for reproduction in a specific environment leave more offspring in the next generation, thereby increasing the proportion of their genes in the population gene pool over time. Natural selection is the principal mechanism of evolutionary change, and is the most important idea in all biology. Natural selection, the unifying concept of life, was first proposed by Charles Darwin, and represents his single greatest contribution to science.
Natural selection occurs in any reproducing population faced with a changing or variable environment. The environment includes not only physical factors such as climate or terrain, but also living factors such as predators, prey, and other members of a population.
Mechanism of Natural Selection
The mechanism of natural selection depends on several phenomena:
• Heredity: Offspring inherit their traits from their parents, in the form of genes.
• Heritable individual variation: Members of a population have slight differences among them, whether in height, eyesight acuity, beak shape, rate of egg production, or other traits that may affect survival and reproduction. If a trait has a genetic basis, it can be passed on to offspring.
• Overproduction of offspring: In any given generation, populations tend to create more progeny than can survive to reproductive age.
• Competition for resources: Because of excess population, individuals must compete for food, nesting sites, mates, or other resources that affect their ability to successfully reproduce.
Given all these factors, natural selection unavoidably occurs. Those members of a population that reproduce the most will, by definition, leave more offspring for the next generation. These offspring inherit their parents' traits, and are therefore also likely to succeed in competition for resources (assuming the environment continues to pose the same challenges as those faced by parents). Over several generations, the proportion of offspring in a population that are descended from the successful ancestor

Uloborid spider eggs and spiderlings. In any given generation, populations tend to create more offspring than can survive to reproductive age.
increases, and traits that made the ancestor successful therefore also increase in frequency. Natural selection leads to adaptation, in which an organism's traits conform to the environment's conditions for existence.
