Plants - biology

• Plant cells have cell walls that are mainly composed of cellulose, which provides support and strength to the cell.
• Photosynthesis is the process where plants convert light energy into chemical energy stored as glucose (C6H12O6). Glucose is then stored as starch.
• Mitochondria produce ATP (energy) through aerobic respiration.
• Stomata are small openings on leaves that allow gases such as carbon dioxide and oxygen to enter and exit the plant.
• Chloroplasts contain chlorophyll, which absorbs light energy during photosynthesis.
• Vacuoles store water, nutrients, and waste products.
• Starch is a polymer of glucose . It is good for storage and energy because it is insoluble and energy dense
• Plants require minerals from soil for healthy growth and development. They enter through the roots by active transport from a low concentration to a high concentration. This requires energy , produced by respiration. A cell carrying out active transport would contain many mitochondria
• Mineral element and how it is used in plants

  nitrogen : making leaves

  phosphorus: making roots

  potassium : making flowers and fruit

  magnesium : making chlorophyll
• Signs that a plant is lacking in these minerals

  nitrogen : upper leaves pale green , lower leaves yellow and dead , weak stem
• Signs that a plant is lacking in these minerals

  phosphorus : purple leaves , small roots
• Signs that a plant is lacking in minerals

  potassium : poor fruit and flower growth , yellow leaves and dead spots
• Signs that a plant is lacking in minerals

  magnesium : upper leaves are normal , lower leaves are pale green or yellow
• Photosynthesis is controlled by the light intensity, temperature, and carbon dioxide concentration
• Factors affecting transpiration

  light : increase transpiration . Stoma opens during the day so more evaporation is possible
• Factors affecting transpiration

  temperature: higher temperature and more evaporation. more kinetic energy, water particles move more and diffuse faster
• Factors affecting transpiration

  wind: more wind , more evaporation. reduces humidity around stoma by blowing water away
• Factors affecting transpiration

  humidity : decreases transpiration. If there is a higher concentration of water outside the leaf, less water will be able to evaporate
• Transpiration is the word used to describe the evaporation of water from the surface of a plant
• Roots are adapted :

  large surface area , root hair cell. Water enters the cell through osmosis.