Assignments and Notice

  Elements and Compounds Everything around us is made up of matter. Matter can be classified into different substances, including elements and compounds. An element is a pure substance made up of only one kind of atom. Examples of elements are oxygen, iron, gold, copper, and hydrogen. Each element has its own properties and cannot be broken down into simpler substances by ordinary chemical methods. A compound is a pure substance formed when two or more different elements combine chemically in a fixed proportion. Water is a common example of a compound. It is made up of hydrogen and oxygen. Similarly, carbon dioxide is made up of carbon and oxygen. The properties of a compound are usually different from the properties of the elements that form it. Elements are represented by symbols, such as O for oxygen, Fe for iron, and Au for gold. Compounds are represented by chemical formulae. For example, H₂O represents water, while CO₂ represents carbon dioxide. Understanding elements...

  The School Garden A school decided to turn an unused piece of land into a garden. The principal asked students to suggest what should be planted. Some students wanted flowers because they would make the school look beautiful. Others suggested vegetables because the school could use them in its lunch programme. A few students thought the land should be used as a playground instead. The school formed a student committee to study the choices. The committee found that the area received enough sunlight but had limited water. They also discovered that vegetables would require regular care, while some local plants could grow with less water. After discussing the advantages and disadvantages, the students suggested planting local vegetables and drought-resistant flowers in different sections of the land. The principal accepted the suggestion and asked the students to review the garden after six months. The students would compare the amount of water used, the cost of maintenance, th...

  The Mobile Phone Question A school was considering whether students should be allowed to bring mobile phones to school. One group of teachers believed that phones could distract students from their studies. They were concerned that students might spend time playing games or using social media during lessons. Another group argued that mobile phones could be useful learning tools. Students could use them to search for information, photograph experiments, use educational applications, and communicate with parents when necessary. They believed that completely banning phones would prevent students from learning how to use technology responsibly. Instead of immediately accepting either position, the school conducted a survey. It found that many students used phones mainly for entertainment, but some used them for educational purposes. The school therefore considered a third option: students could bring phones but would have to keep them switched off during lessons unless a teache...

   Physiological Structure and Life Processes Which organelle is known as the powerhouse of the cell? A. Nucleus B. Ribosome C. Mitochondria D. Vacuole Which tissue is responsible for transporting water and minerals in plants? A. Phloem B. Xylem C. Epidermis D. Parenchyma Which part of the human respiratory system is the main site of gaseous exchange? A. Trachea B. Bronchus C. Alveoli D. Larynx Which component of blood transports oxygen to body tissues? A. Plasma B. Platelets C. White blood cells D. Red blood cells What is the main function of the kidneys? A. Pumping blood B. Digesting food C. Removing nitrogenous wastes from blood D. Producing oxygen Which process allows green plants to prepare their own food? A. Respiration B. Transpiration C. Photosynthesis D. Excretion Which hormone regulates the l...