Concept explainers
To determine:
The tissue in which it is expected to find the radioactive material immediately after exposure to the labeled carbon and during transport if a scientist has exposed a leaf to
Concept introduction:
Phloem sap is the organic compound consisting sugars, amino acids, hormones, enzymes water and minerals. The sugar is mostly dissolved carbohydrates like sucrose. It is synthesized at source part of the plant. The source parts of the plant are capable of synthesizing sugars in the presence of sunlight by the process of photosynthesis. The photosynthetic cells present in leaves are capable of photosynthesis. Thus, phloem cells originate in the photosynthetic cells only.
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Biology: Concepts and Investigations
- What is the BEST explanation for why thylakoid membranes are flat and stacked? A. to fit more into a chloroplast B. to increase surface area for light absorption and cross- membrane traffic C. to increase the color of the leaf as camouflage from herbivores D. to hold more ATParrow_forwardIn which compartment of the plant cell do the light-independent reactions of photosynthesis take place? a. thylakoid b. stroma c. outer membrane d. mesophyllarrow_forwardPlant leaves contain openings called stomata, which allow the diffusion of ?arrow_forward
- If you don’t water a plant, it will eventually die. Explain why the absence of water halts photosynthesis. Also, cells that use aerobic cellular respiration, like humans, do not produce ATP at normal levels without oxygen gas. Discuss why this is so.arrow_forwardUnder what conditions does plant tissue experience lack of oxygen? How is ATP generated from glucose without oxygen?arrow_forwardPhotosynthesis directly opposes respiration in determining how plants influence atmospheric CO2 concentrations. When a leaf is in the light, both photosynthesis and respiration are occurring simultaneously. The data in the Table were collected from the leaf of a sagebrush plant that was enclosed in a chamber that measures the rate of CO2 exchange. The same leaf was used to collect the data in Interpret the Data in Chapter 7. Respiration is shown as a negative and photosynthesis as a positive rate of CO2 exchange. The net photosynthesis rate is the amount of CO2 (in micromoles per square meter per second) assimilated by the leaf while respiration is occurring; a positive value indicates more photosynthesis is occurring than respiration. The light exposed to the leaf is quantified as the number of photons in the 400 to 700 nm wavelength, the photosynthetic photon flux density (PPFD); 2,000 mol/m2/s is equivalent to the amount of light occurring at midday in full Sun. Observation Photosynthetic Photon Flux Density (PPFD) (mol/m2/s) Net Photosynthesis (mol/m2/s) 1 2,000 9.1 2 1,500 8.4 3 1,250 8.2 4 1,000 7.4 5 750 6.3 6 500 4.8 7 250 2.2 8 0 -2.0 Why is net photosynthesis negative when PPFD is zero? Looking at the respiration data from Interpret the Data in Chapter 7, at what temperature do you think these data were collected? Source: Data based on unpublished research by Brent Ewers, University of Wyoming.arrow_forward
- Plant roots are adapted as storage organ( such as potatoes and carrots)Typically photosynthesize during the summer and remain dormant underground during winter. Explain how sugar transport in such a plant would be different during summer, when the plant is photosynthesizing and in the spring when new growth is coming uparrow_forwardWhich of the following membrane activities requires energy from ATP hydrolysis? Group of answer choices water uptake of plants from roots to shoots movement of water using aquaporin absorption of dissolved nutrients in the small intestine transport of oxygen through the phospholipid layerarrow_forwardPredict what will happen to the transportation of water and minerals through the plasma membrane if the root was poisoned and no cellular respiration occurredarrow_forward
- Animals typically use fats in adipose tissues for longterm energy storage, whereas plants use starch in roots. How do animals benefit from using fat? How do plants benefit from using starch? Name two plants that storeenergy for many years. How long is long-term storage for these species? What two plant parts often use fats and why? Storage tissue in enlarged roots is vascularized. How is that important to the plant?arrow_forwardWhat are ways in which plants accomplish tissue-level transport?a. transmembrane transport of solutes from one cell to anotherb. symplastic transport of materials from one cell to another viaplasmodesmatac. apoplastic transport of water and dissolved solutes through cell wallsand intercellular spacesd. All of the above are used for tissue-level transport.e. None of the above are used for tissue-level transport.arrow_forwardIn an oak tree leaf 80 feet above the ground a cell of the spongy mesophyll is Photosynthesizing explain how the rest of the tree is meeting the physiological needs of the cell.arrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning