KSM NEET - BIOLOGY

  Viruses are small infectious agents that can only replicate inside living host cells. They are composed of a nucleic acid genome, either DNA or RNA, surrounded by a protein coat called a capsid. Some viruses also have an envelope, which is a lipid membrane derived from the host cell membrane that surrounds the capsid. The genetic material of viruses can be either single-stranded or double-stranded, and can be either RNA or DNA. Some viruses, such as retroviruses, have RNA genomes that are reverse transcribed into DNA upon entering the host cell. Others, such as herpesviruses, have large DNA genomes. Some common viral diseases include: Influenza : a respiratory illness caused by the influenza virus, which can lead to fever, cough, sore throat, and body aches. HIV/AIDS : a viral infection caused by the human immunodeficiency virus (HIV), which attacks the immune system and can lead to acquired immunodeficiency syndrome (AIDS). Hepatitis : a group of viral infections that affect the...

  Diatoms are unicellular algae that have a unique cell wall made of silica, a chemical compound that is hard and brittle. The cell wall of a diatom is called a frustule, and it consists of two overlapping valves that fit together like a pillbox. The frustule is perforated by small pores that allow for the exchange of gases and nutrients. The frustule is composed of two layers, an outer layer called the epitheca and an inner layer called the hypotheca. The two layers are fused together at the edges to form a tight seal that helps to maintain the structural integrity of the cell. The silica that makes up the frustule is arranged in intricate patterns that are characteristic of each species of diatom. These patterns can be seen under a microscope and are used to identify different species of diatoms. The unique structure of the diatom frustule makes it an important component of aquatic ecosystems, where it serves as a major source of food for many marine organisms. Additionally, the ...

  Classification systems have undergone several changes over time due to various reasons, including advancements in scientific knowledge and changes in scientific theories, discovery of new species, and improvements in technology. One of the earliest classification systems was developed by Aristotle in the fourth century BC, which was based on physical characteristics such as size, shape, and color, and were primarily used for identification and naming of species. Later, in the 18th century, Swedish botanist Carl Linnaeus developed the Linnaean classification system, which is still in use today. This system organizes living organisms into hierarchical categories based on their physical characteristics and evolutionary history. Over time, however, scientists began to realize that physical characteristics alone were not sufficient for classification, and that molecular and genetic information was also important. As a result, new classification systems based on DNA sequencing and ot...

  Age: One simple way to classify people is by age, such as children, teenagers, adults, and seniors. Gender: Another way to classify people is by gender, such as male, female, or non-binary. Occupation: People can be classified by their occupation, such as doctors, teachers, engineers, and so on. Education level: People can also be classified by their level of education, such as high school graduates, college graduates, or postgraduate degree holders. Cultural background: People can be classified by their cultural background, such as nationality, ethnicity, religion, or language. Personality traits: People can be classified by their personality traits, such as introverted, extroverted, analytical, creative, and so on.

Classification systems for living organisms are not fixed or static, but rather, they are constantly changing and evolving as our knowledge of the natural world expands. The reasons for these changes can vary, but here are some common reasons why classification systems may change: New discoveries: As scientists discover new species and gain a better understanding of existing ones, they may need to update the classification system to reflect these new findings. For example, new DNA sequencing techniques have led to the discovery of many new species that were previously unknown. Changes in scientific understanding: As our understanding of the relationships between different organisms evolves, classification systems may need to be revised to reflect these changes. For example, the development of evolutionary theory has led to changes in how organisms are classified based on their evolutionary history. Advances in technology: Advances in technology, such as new imaging techniques and m...

Living organisms are classified in order to organize and understand the vast diversity of life on Earth. By grouping organisms based on their shared characteristics and evolutionary history, we can better understand the relationships between different species and how they have evolved over time. The system of classification that is commonly used today is called the Linnaean classification system, which was developed by Swedish botanist Carl Linnaeus in the 18th century. This system organizes organisms into a hierarchy of increasingly specific categories, starting with the broadest category , the kingdom, and then moving down through phylum, class, order, family, genus, and species. Classification allows us to assign a specific name to each organism and helps us to easily identify and communicate information about it. For example, by knowing an organism's classification, we can make predictions about its behavior, diet, and habitat, and we can compare it to other organisms that ...

  Living organisms are entities that are characterized by certain fundamental features, including: They are composed of one or more cells: Living organisms can be made up of a single cell (unicellular) or multiple cells (multicellular). They exhibit metabolism : Living organisms use energy to carry out their life processes, including obtaining nutrients, synthesizing molecules, and eliminating waste. They respond to stimuli : Living organisms can sense and respond to changes in their environment, such as light, temperature, and chemicals. They have the ability to grow and reproduce: Living organisms are capable of growing and developing, as well as producing offspring that are similar to themselves. They exhibit homeostasis: Living organisms maintain a stable internal environment, even in the face of changing external conditions. Examples of living organisms include plants, animals, fungi, bacteria, and archaea. These organisms exhibit a diverse range of characteristics and are f...