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NEET Important Notes on Organisms and Population

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Last updated date: 25th Apr 2024
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Organisms and Population

Availability of the right kind of notes is the biggest dilemma of student life. Sometimes they buy loose notes from the market and realize it is not helping them or sometimes the price of good notes is really high! What can one probably do in such a situation?


Well, Vedantu has the answer to that question.  With the intent to provide high-quality notes to the students, Vedantu has come up with NEET Important Notes on Organisms and Population.  The notes could be downloaded in PDF format by the students.  It could be accessed through any apple, android, or windows device. To the surprise of the students, resources are totally free of cost, which satisfies Vedantu’s intent to provide affordable education to all.  Now money and location are no more an obstacle in their pursuit of quality education. Download NEET Important Notes on Organisms and Population and ease your NEET preparation.

 

Notes

The German Philosopher, Professor, Naturalist, and Biologist ‘Ernst Haeckel’ take credit for coining the term “Ecology”. At the biophysical level of the environment, ecology is the natural state of interaction, reproduction, and survival across abiotic and biotic components. This level is also called the ‘Organismic Phase.’ 


For living species, life on earth is both comfortable and extreme, due to multiple internal and external factors. Understanding the concept of Organisms and Populations together is an interesting and also an informational piece of content. 


Hence, the following are some of the important pointers, factors, characteristics, and other related notes from the organism and population NCERT text versions. After a thorough reading, you can also test your understanding of the ecology concepts, by trying out the FAQs section at the end of this learning module. 


2 Important Terms to know 

Before we go for deeper learning, the terms ‘Habitat’ and ‘Niche’ are basic and significant ones inside the study of environmental sciences, ecology, and biology. Given below are the definitions for the same.

  • HABITAT: The natural surrounding/environment of a given organism is its Habitat. By thriving here, organisms adapt and develop their suitable survival mechanisms and defense system at times of threat.

  • NICHE: All the external and internal resources or factors that are required by a given organism in its natural environment is Niche. Niche gives an idea about an organism’s functional role in that particular ecosystem/habitat.

 

The 4 Major Abiotic Factors with 5 Tolerances

In any particular ecosystem, Light, Soil, Water, and Temperature are the 4 major abiotic factors noted. The tolerance to these factors are listed as 5 below:

  • Stenothermal- When the temperature levels cannot be tolerated (intolerance).

  • Eurythermal- When the temperature and its changes are bearable (tolerance).

  • Photoperiodism- Plants are directly influenced by the amount of sunlight they acquire for flowering purposes. This varies across plants as short-day, long-day, and some-day neutral plants.  Some-day ones do not have any impact on its flowering process from sunlight. 

  • Stenohaline- When the changes in salinity cannot be well-managed (intolerance).

  • Euryhaline- When the salinity and the changes are supportable (tolerance).


Species tend to have their defense mechanism and other coping strategies to overcome and balance the changes that happen in their natural habitat (or at least inside their niche). Some of the best responses to the mentioned above abiotic factors are given in the following context.

 

What are the Possible Responses to Abiotic Factors?

  • Adaptation: Adapting to the new ecosystem is the most common way of responding to changes that occur in the abiotic system. Species can adapt physiologically, morphologically or even behaviourally. 

  • Suspended Animation: In the case of algae, fungi, and many other microorganisms, they try to avoid unfavorable changes/conditions by forming a thick-walled spore. For example, seed dormancy is a form of suspension to give protection to its seeds from desiccation. 

  • Conforming: Conform or confirming is observed in a majority of animals and plants when they are unable to maintain their temperature internally like that of poikilotherms. Conformers are the extreme opposite to Homeotherm (animals that maintain their thermal homeostasis).

  • Allen’s Rule: For minimizing heat loss, mammals in colder regions or climates have smaller ears and limbs. Blubber is a classic example. 

  • Migration: Predominantly noted in birds, species mirage, i.e. move from 1 region to another area temporarily. Albatross, Osprey, Siberian Crane, Eurasia Blackcap are some of the examples of birds that migrate. 

 

Important Notes on Organisms and Populations

Organisms and Populations are directly proportional to each other and changes in 1 system affect the other. Some of the important pointers regarding population along with organisms as a complete data set are given in the following:

  1.  In a specific geographical location, the number of inbreeding species count refers to its ‘total population.’  

  2. Age pyramid, Sex ratio, Birth rate, Death rate, immigrating new individuals, people who emigrate, etc. are some of the ‘Population Attributes.’ 

  3. The percent (%) coverage or biomass for a set of Organisms and Populations is called ‘Population Density’.

  4. Counting each organism is not possible to calculate the population density. Indirect means such as fecal pellets of a tiger or the count of fish caught per 1 trap or the pugmarks left by an animal are essential. 

  5.  Mortality, Natality, Immigration, and Immigration are the 4 factors that affect population growth. This can be evaluated by the formula Nt+1 = Nt + (B+I)–(D+E)(B+I)–(D+E). 

  6. Population interaction includes Mutualism (all species win), Competition (both species lose), Parasitism (1 harmed and 1 win), Predation (1 harmed and 1 win), Commensalism (1 harmed and 1 not affected), and Ammensalism (1 harmed and the other not affected). 

 

The Intelligent Way to study

In today’s day, smart work is more popular than hard work. It is important to have hard-working values but one must not forget the value of smart work as well. Undoubtedly having good quality is the smartest strategy for NEET that one can follow. NEET Important Notes on Organisms and Population available on Vedantu place students in an advantageous position. One can study very smartly and touch all the important topics of the examination in a very less time and derive greater results.


 It further improves management and planning skills on the student’s part which later helps them confidently face the exam and remain calm throughout. Acquiring good quality revision notes as provided by Vedantu is undeniably a step forward in the right direction that benefits the students from the 360-degree perspective.  

 

Expert Teachers

The NEET Important Notes on Organisms and Population are prepared by the best teachers in the field. While studying for the NEET exam, one needs to cover up the syllabus in the shortest time possible. It is very hard to touch each and every aspect of the syllabus, and at the same time, one has to practice previous year's questions and revise too.


Taking care of all the above aspects, the teachers at Vedantu have very meticulously prepared the notes which are equipped with the feature to save the time of the students and also allow them to revise the notes multiple times. Despite being crisp, these notes touch all the important aspects of the topic discussed.

 

Methods and Approach

There are many ways to do well in exams. However, one must not confuse that it is easy to do well in the exam. In the beginning, know your weaknesses and strengths.  To score well in exams the student should practice a lot. They must regularly go to school and ask questions from their teachers and clear doubts. Sitting for a group study and solving common problems or solving practice questions helps too. There is a possibility that group studies are not possible due to covid-19 norms in the student’s location. In that case, one can opt for the option of zoom video calls.


Apart from that, a student can decide to choose to be in Vedantu too. Vedantu which is an online teaching platform is a home for India’s top NEET educators. Students are encouraged to visit Vedantu’s website and explore many courses related to the NEET examination. There are also a lot of free resources that a student can find on the website and benefit from it with no registration or sign-ups required beforehand.

 

Motivation  

It is highly important for a student’s stay motivated throughout their preparation phase. To serve this purpose, there are a couple of methods that a student can follow to keep the spirit always high.

  • Listen to motivational music

  • Read inspiring stories of the toppers

  • Listen to wise teachers and follow their advice.

  • Do yoga or meditation

  • Running is the best exercise that one can pursue to keep oneself always motivated.

FAQs on NEET Important Notes on Organisms and Population

1. What is Hibernation?

The Hibernation is a form of resting phase, where animals escape from cold weather by hiding inside their shelters for a longer duration. This form of a survival strategy is called Winter Sleep and is observed in organisms such as rodents, bats, and squirrels.

2. What are the Attributes that a Population has but Individuals do not Possess?

Birth rate (natality), the death rate (mortality), age distribution, sex ratio (females: males), and population density are some of the attributes that a population has but individuals do not possess.

3. Name a Few Plants that have a Chemical Defense Mechanism.

Nicotine, quinine, caffeine, opium, and caltrops are some of the plants that release noxious chemical substances as a form of defense mechanism.

4. What is the Difference Between an Endotherm and Exotherm?

Endotherms are animals that have a body temperature that is different from their environment. Examples include fishes and reptiles. The body temperature will remain constant in the case of exothermic organisms (exothermic). Many mammals and bird species are exotherms.

5. What are Camouflaging Organisms?

Also referred to as Cryptic Coloring, Camouflaging organisms are species that have a tactic defense mechanism of escaping from their predators by disguising their location, movement, or identity. Madagascar and Panther’s chameleon species possess this super-defense of changing their body color to the environment. Even lizards, jaguars, and frogs are camouflaging organisms.