BIO FLIPBOOK: MOLECULES OF LIFE & CELL STRUCTURES AND FUNCTIONSSB015 2026/2027 Nama: Nur Aisyah Ibtisam Binti Mohamad Sufian Matric number: MS2513171200 Practicum: K1T01B Lecturer’s name: Madam Tamilarasi A/P Rajaram Set: A
MAIN TYPES OFMOLECULES OF LIFE PROTEINS CARBOHYDRATESRNA and DNA MOLECULES WATER LIPIDS I. [5 marks]
II.DESCRIBE THE STRUCTURE OF WATER MOLECULE104.5°StructureConsists of an oxygen atom & two hydrogen atoms. Two hydrogen atoms form polar covalent bonds (sharing of electrons) wih an oxygen atom. Water is a polar molecule. Angle between 2 hydrogen atoms is 104.5°. Water molecules are held together by a hydrogen bond. Each water molecule can form hydrogen bonds with up to maximum 4 other water molecules. [10 marks]
Agricultural III.EXPLAIN ON OSMOSIS Definition of osmosis: Is a movement of water molecules from higher water potential region to lower water potential region across a selectively permeable membrane until equilibrium is reached.
DIFFERENCES OSMOSIS SIMPLE DIFFUSION FACILITATED DIFFUSION TYPE OF MOLECULE Water molecule only Small, non-charged, lipid-soluble, hydrophobic molecules Larger, charged, polar, hydrophilic molecules PATHWAY MEMBRANE Aquaporins (protein) Phospholipid bilayer Channel proteins or carrier proteins SIMILARITIES Osmosis, simple diffusion and facilitated diffusion all are passive transport processes. Osmosis, simple diffusion and facilitated diffusion all no ATP required. Osmosis, simple diffusion and facilitated diffusion all molecules move down their concentration gradient. [10 marks]COMPARE OSMOSIS WITH SIMPLE DIFFUSION AND FACILITATED DIFFUSION
Body temperature may rise during hot days. How can sweating helps to give cooling effect for our body? What about animals that do not sweat such as elephants? Give explanation by applying the concept related to the properties of water?? ?? Sweating helps to cool the body because sweat is mainly made of water. Water has a high latent heat of vaporisation, so it absorbs a large amount of heat from the body to evaporate into water vapour. A high amount of heat energy (580 calories of heat) is required to turn 1g of water from liquid state into water vapor. As sweat evaporates from the surface of the skin, heat is removed from the body, causing the body temperature to decrease and producing a cooling effect. The heat energy is required to break hydrogen bonds and separate the water molecules. Animals such as elephants, do not sweat much, so they cool themselves by spraying water on their bodies, bathing, or covering themselves with wet mud. As the body evaporates, it absorbs a large amount of heat from their bodies due to water’s high latent heat of vaporisation, helping to lower their body temperature. Elephants also flap their large ears to increase heat loss to the surrounding air. This may also prevent their bodies from overheating during hot day and helps keep their animal cool. [10 marks]