How do producers get the substances they need? B3.2 Flashcards
What is osmosis?
Osmosis is the movement of water across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
Describe the function of xylem and phloem in plants.
Xylem transports water and minerals from roots to leaves, and phloem transports sugars produced during photosynthesis to other parts of the plant.
What is transpiration?
Transpiration is the process by which water is absorbed by plant roots, moves up through the plant, and evaporates from the leaves.
What substances do photosynthetic organisms transport in and out of their cells?
Photosynthetic organisms take in carbon dioxide, water, and minerals needed for photosynthesis and growth. They release oxygen (as a byproduct of photosynthesis) and glucose (used for energy and growth).
What is active transport?
Active transport is the movement of particles from a low concentration to a high concentration against the concentration gradient. It requires energy from respiration.
What is diffusion?
Diffusion is the movement of particles from an area of high concentration to an area of low concentration until they are evenly spread. It is a passive process and does not require energy.
Describe a practical investigation into diffusion.
One common investigation is to observe how colored substances, like food dye or potassium permanganate, spread through a gel or water over time, showing diffusion from areas of high to low concentration.
Describe a practical investigation into osmosis.
An osmosis experiment might involve placing potato slices in solutions of different salt concentrations. The potato gains or loses water by osmosis, causing it to increase or decrease in mass.
How do partially-permeable membranes help in diffusion and osmosis?
Partially-permeable membranes allow only certain molecules (like water in osmosis) to pass through, enabling cells to control the movement of substances in and out.
How are root hair cells adapted for their function?
Root hair cells have a large surface area to absorb more water and minerals. They also have thin cell walls for easier absorption and use active transport to take in minerals from the soil.
How is the xylem adapted to its function?
Xylem vessels are made of dead, hollow cells that form tubes to transport water and minerals from roots to leaves. They have thick cell walls strengthened with lignin for support.
How is the phloem adapted to its function?
Phloem tubes are made of living cells with sieve plates, allowing the movement of sugars and nutrients throughout the plant (a process called translocation).
How can you use a light microscope to observe the xylem and phloem?
Place a thin section of a plant stem on a microscope slide, add a drop of water, and cover with a coverslip. Use the light microscope at a low magnification to locate the xylem and phloem cells.
What is transpiration?
Transpiration is the evaporation of water from the leaves of a plant, primarily through the stomata. It helps pull water up from the roots through the xylem.
What is translocation?
Translocation is the movement of sugars and other nutrients through the phloem from where they are made (in the leaves) to other parts of the plant where they are needed.
