IGCSE Biology MCQ Quiz! Exam

The formula for calculating magnification is given by Magnification = Image size / Actual size. This formula represents the ratio of the size of the image produced by an optical system to the actual size of the object being observed. By dividing the image size by the actual size, we can determine the degree of magnification achieved.

The structures that are only found in a plant cell are chloroplasts, cell walls, and permanent vacuoles. Chloroplasts are responsible for photosynthesis, converting sunlight into energy. Cell walls provide support and protection to the cell. Permanent vacuoles store water and nutrients. The nucleus, cell membrane, and cytoplasm are found in both plant and animal cells.

The rate of transpiration, which is the process of water movement through a plant and its evaporation from aerial parts, is affected by several factors. Temperature plays a significant role as it increases the rate of evaporation and therefore transpiration. Humidity affects transpiration by creating a concentration gradient between the leaf surface and the surrounding air. Higher humidity reduces the rate of transpiration. Wind can increase transpiration by removing the boundary layer of humid air around the leaf surface. Light intensity affects the opening and closing of stomata, which in turn affects transpiration. Therefore, all these factors - temperature, humidity, wind, and light intensity - have a direct impact on the rate of transpiration.

The pulmonary artery carries deoxygenated blood from the heart to the lungs to be oxygenated. The hepatic vein carries deoxygenated blood from the liver back to the heart. The hepatic portal vein carries deoxygenated blood from the digestive organs to the liver for detoxification and nutrient processing. The vena cava carries deoxygenated blood from the body back to the heart.

THROUGH A PARTIALLY PERMEABLE MEMBRANE!!

Glucose, galactose, and fructose are simple sugars because they consist of a single sugar molecule or monosaccharide. Sucrose, lactose, starch, and glycogen are complex sugars or polysaccharides because they are made up of multiple sugar molecules bonded together. Cellulose is also a complex sugar and a type of fiber found in plant cell walls.

The rate of diffusion is affected by several factors. Temperature plays a significant role in diffusion as higher temperatures increase the kinetic energy of particles, leading to faster movement and therefore faster diffusion. Particle size affects diffusion because smaller particles have a larger surface area to volume ratio, allowing for quicker diffusion. Surface area also influences diffusion as a larger surface area provides more space for particles to diffuse. Concentration gradient is another factor as a larger difference in concentration between two areas leads to faster diffusion. Lastly, distance affects diffusion as shorter distances allow for quicker diffusion.