1 / 10

Module B4

Module B4 . It’s a Green World . Transparent. Structure of a Leaf Chloroplasts Diffusion Internal SA/volume ratio large Osmosis : flaccid, plasmolysed, turgid –H = crenation, lysis

adamdaniel
Télécharger la présentation

Module B4

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Module B4 It’s a Green World

  2. Transparent Structure of a Leaf Chloroplasts Diffusion Internal SA/volume ratio large Osmosis : flaccid, plasmolysed, turgid –H = crenation, lysis Transpiration: cooling, photosynthesis, support, movement of minerals, stomatal apertures – guard cell turgidity and number

  3. Xylem –hollow lumen, dead cells - water Phloem – column of living cells- food substances Transpiration –evaporation and diffusion of water - from roots to shoots and leaves – light intensity, temp, air movement, humidity Translocation - to stems and storage tissues Vascular bundles

  4. Minerals – active transport (low to high, uses energy) through root hairs Nitrogen/nitrates = amino acids – proteins for cell growth – Yellow leaves & poor growth Phosphorous/phosphates = synthesis of DNA, cell membranes for respiration & growth – poor roots, discoloured leaves Potassium - enzymes in photo. & respiration – poor flower and fruit growth, discoloured leaves Magnesium = make chlorophyll for photo. – yellow leaves

  5. Energy Flow Pyramids of number and biomass Effect of removing one organism from a web or chain Energy is transferred at each trophic level – heat from respiration and egestion – calculate efficiency of energy transfer Biomass - burning trees, fermenting biomass – renewable, reduces pollution, energy self-reliance – uses: food for people/livestock, fuel, growing seeds

  6. Farming Intensive - producing as much food as possible – improves energy efficiency by energy not going to : competing plants, pests, lost as heat or movement (pens) Pollution – pesticides in food chain (bioaccumulation), harming non-pests Hydroponics - uses glasshouse tomatoes, barren soil – adv. Control of disease, control of mineral levels – disadv. Lack of support, addition of fertilisers Organic Farming - uses manure & compost, crop rotation, legumes, weeding, varying seed planting times, biological control(adv, & disadv.)

  7. Decay Rate of decay is affected by: temp, amount of oxygen, amount of water – these factors affect microbial respiration, growth and reproduction (producing sewage & compost) Detritivores (earthworms, maggots, woodlice) feed on detritus (dead/decaying material) – produce larger surface area- increase rate of decay Saprophyte – live on dead organic matter e.g bacteria & fungi Food preservation - canning, cooling, freezing, drying, salt/sugar, vinegar

  8. Recycling Nutrients recycled through death and decay are Carbon and Nitrogen

  9. Air is mainly composed of Nitrogen (78%), but is too unreactive to be used

  10. Higher only Carbon is recycled in the sea – marine organisms make shells of carbonates – shells= limestone – carbon returns to CO2 through weathering and volcanic eruption. Nitrogen – decomposers convert protein & urea to ammonia, nitrifying bacteria convert ammonia to nitrates, denitrifying bacteria convert nitrates to N gas – nitrogen fixation occurs due to lightning or bacteria in root nodules

More Related