Sunday, July 18, 2021

What is Growth Habit?

 Question:

What is Growth Habit?

Explanation:

In horticulture, the term growth habits refer to the plant’s growth and its development or change in the plant’s height, shape and the kind of growth it undergoes. There are genetic factors as well as environmental factors which play an important role in their growth habit.

For instance, interaction with various animals influences the way plants adapt to their environment. From an evolutionary perspective, growth habits have the function of ensuring the survival and adaptation of plants in various habitats, consequently increasing the chances of successfully passing on the genes to the next generation.

How are climbers different from creepers?

 Question:

How are climbers different from creepers?

Explanation:

The main difference between climbers and creepers are:
Creepers spread their stem, leaves horizontally along with the soil on the ground and also bear flowers along with the fruits on the ground. The leaves of the creepers produce fibre-like roots which fix the plant to the ground and provide external support to grow further.
Climbers are plants with a tender stem which grow with the help of external support. These plants produce a twine or hook from their leaves to climb. Some plants produce special roots that serve as the holdfasts to climb around certain objects.

What are the important sources of organic compounds?

 The main sources of organic compounds are plant and animal kingdoms. Organic compounds are isolated from these two natural sources by solvent extraction followed by purification. These two sources are again converted naturally into petroleum oil, natural gas, and coal. Organic compounds always contain carbon along with other elements that are needed for living organisms to function. All organic compounds are one time came from plants or animals many of our most important substance are still derived from these sources directly or indirectly.

Nowadays synthesis is the most important source of organic compounds. So, the sources of organic compounds, in short, are-

Plants and animals: By using suitable methods of isolation most of the organic compounds were obtained directly from plants and animals in the past and at present, these methods are continuing. Many organic compounds are obtained straightforwardly from plant and animals sources by a suitable method of isolation a few common examples are carbohydrates (cellulose, sugar, and starches) proteins (silk, wool, casein, and food proteins) fats and oils (cottonseed soybean oils lard, butter) alkaloids (quinine, morphine, strychnine) hormones, vitamins, perfumes, flavors and resins. There are four major categories are found in all living things: carbohydrates, lipids, proteins, and nucleic acids. The compounds which are obtained from these sources are –

  • Carbohydrates: Cellulose, starch, sugar, lactose, etc.
  • Protein: Food proteins, wool, silk, casein, etc.
  • Fats and oils: Cottonseed, soya bean oil, lard, butter, etc.
  • Alkaloids: Quinine, morphine, ephedrine, etc.
  • Perfumes: Citral, limonen, mascone, etc.
  • Vitamins: Vit. C, B2, B6, etc.
  • Hormones, Resins, rubber, etc.
Petroleum oil and natural gasHundreds of hydrocarbons such as methane, octane, kerosene, petrol, benzene, toluene and other petrochemicals are obtained which are further used as raw materials of polymers, plastics, synthetic rubber, explosives, etc. Natural gas and petroleum are now the key sources of organic compounds they are used as fuels and also, through the synthetic organic reaction for the production of hundreds of valuable organic substances such as solvents, synthetic rubber, explosive, and plastic. The main energy source, fuel is obtained from natural gas and crude petroleum oil. Urea is a good example which is obtained from natural gas on our planet.

Coal: Another fossil fuel coal is the major source of organic compounds, coal-tar are raw materials of many aromatic compounds. Coal is another key source of organic compounds. It yields coke and coal-tar on hydrolysis or destructive distillation more than 200 organic compounds have been in a straight line isolated from coal-tar, these coal-tar products from the starting resources for the manufacture of thousands of helpful aromatic compounds, including perfumes, drugs, dyes, photographic developers, and other.

Synthesis: Simple organic compounds resulting from petroleum or coals have been transformed into thousands of helpful resources by a synthetic process. Many useful organic compounds including drugs, vitamins, plastics, dyes, etc. are prepared from simple raw materials by multistep synthesis. Many examples might be cited of synthetic organic compounds replacing those obtained from natural sources, such as dyes, rubber, fibers, plastic, drugs, vitamins in many cases the synthetic materials are better to the natural compounds replaced for example, synthetic dyes are greater to those of usual source in other cases the synthetic resources are completely unidentified in nature and fill the requirements not contented are completely other sources. Examples are ether glycol; aspirin, and sulfur drugs, synthetic organic chemistry touches almost every phase of life.

Hence, the important sources of organic compounds are plant and animal kingdoms.

What is genetic drift?

Question:

What is genetic drift?

Explanation:

Genetic drift is a mechanism of evolution in which the allele frequencies change over generations as a matter of chance. It occurs in populations of all sizes but its effect is the maximum in a small population. Genetic drift is observed when there is a sudden decline in the population due to natural disasters (bottleneck effect), or when a new population separates from the original population to form a colony (founder effect). Genetic drift does not take into account whether the allele is beneficial or harmful to the individual carrying it. It is possible that a beneficial allele is lost and a harmful allele persists.

State the Hardy-Weinberg principle.

 Question:

 State the Hardy-Weinberg principle.

Explanation:

The Hardy-Weinberg principle states that in a large population not affected by the evolutionary processes such as mutation, selection or migration, the allele frequencies and the genotype frequencies are constant from one generation to the other. The principle can be explained by the simple equation: 

(p+q)= p+q+ 2pq = 1 

Where, 

p = frequency of allele  

q = frequency of allele  

p= frequency of individual 

q= frequency of individual  

2pq = frequency of individual.

What is the driving force behind divergent evolution? Explain.

Question:

What is the driving force behind divergent evolution? Explain.

Explanation:

Adaptation is the driving force behind divergent evolution. Divergent evolution is the phenomenon in which the organisms descending from common ancestors evolve gradually into a new species. The new species thus formed adapt themselves to the new habitat and environmental conditions. For eg., the forelimbs of bats, cheetahs, whales and humans have the same anatomical structures but perform different functions. Thus, in these animals, the same structure evolved into different forms according to the needs of the animals.

What are the types of evolution

Question:

What are the types of evolution

Explanation:

The different types of evolution are:

  1. Convergent evolution– It is the process, which evolves independently, under similar selection pressures. For example, flying insects, birds and other flying species have all evolved the ability to fly, but independently of each other.
  2. Coevolution evolution–It is the process in which two or more species evolve in tandem by exerting selection pressures on each other. For example, host and parasites, predators and prey,  flowering plants and pollinating insects and mutualistic or symbiotic interactions.
  3. Adaptive radiation–It is the process in which a species splits into a number of new forms when a change in the environment makes new resources available or creates new environmental challenges. For example, finches on the Galapagos Islands have developed different shaped beaks to take advantage of the different kinds of food available on different islands.

What is Mutualism? write type and example.

Question: What is Mutualism? write type and example. Answer: Mutualism: The term mutualism can be simply defined as a relationship in which ...