• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Structure of the leaf and its adaptation for photosynthesis

Extracts from this document...


Structure of the leaf and its adaptation for photosynthesis The leaf is the organ of a plant in which photosynthesis occurs. For photosynthesis to occur, the chlorophyll, mostly found in leaves, must absorb light energy and transform it into chemical energy used in the synthesis of carbohydrates from water and carbon dioxide. Therefore, the leaf has many adaptations for photosynthesis. Firstly, the structure of a leaf is optimized for absorbing light and carrying out photosynthesis. A typical leaf consists of a lamina, petiole and a leaf stalk. The lamina of a leaf has a large flat surface area with chlorophyll located close to the top surface, for maximum light absorption. The petiole holds the lamina away from the stem so that the lamina can obtain sufficient sunlight and air. ...read more.


When water pressure is high, the thin outer walls of the cells are forced into a curved shape. This pulls the think inner walls of the guard cells away from one another, opening the stoma. When water pressure decreases, the inner walls pull together and the stoma closes. Guard cells respond to conditions in the environment, such as wind and temperature, helping to maintain homeostasis within a leaf. Leaves are covered on the top and bottom by epidermis made of a layer of tough, irregularly shaped cells. The epidermis of many leaves is also covered by the cuticle and lack chloroplast. Together, the epidermis and the cuticle form a waterproof barrier that protects tissues, limits the loss of water through evaporation and help focus the light onto the mesophyll layers, right below the upper epidermis. ...read more.


This also means that water evaporates from these surfaces and is lost to the atmosphere, a process called transpiration. The water would be replaced by water drawn into the leaf through xylem vessels in the vascular tissue. The vascular tissue of leaves are connected directly to the vascular tissues of stems, making them part of the plant's transport system. In leaves, xylem and phloem tissues are gathered together into bundles that run from the stem into the petiole and end among the mesophyll cells. The xylem brings water and dissolved mineral salts to the leaf from the soil via the roots and the stem. Once out of the veins, these raw materials diffuse from cell to cell right through the mesophyll of the leaf. Once the chlorophyll receives the essential raw materials, the manufactured food such as glucose made would then be transported as sucrose via the phloem to all the plant cells. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Green Plants as Organisms section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Green Plants as Organisms essays

  1. Find out where the stomata are located, on the upper or lower epidermis of ...

    The mechanism of stomata opening and closure At first glance the mechanism causing this diurnal opening and closing might seem obvious. Unlike other epidermal cells, the guard cells have chloroplasts and at daybreak they start photosynthesizing; this leads to an accumulation of sugar in the guard cells whose osmotic pressure increases.

  2. How temperature affects the rate of photosynthesis.

    Comparing the accuracy of the two graphs, it can be said that both of them are similar in accuracy because both the anomalous results are only present at 25 oC and both the anomalies lie above the line of best fit.

  1. Compare stomatal densities of the upper and lower epidermis of a leaf.

    Their leaves grow horizontally and as a result most or all of the stomata are found on the lower epidermis. This is because of the cuticle found on the upper epidermis. If there was no cuticle, stomata wouldn't be necessary as gaseous exchange would be much more efficient, however, then transpiration could not be controlled.

  2. How did Leamington develop into a typical spa town of the mid nineteenth century?

    For a town to be able to take the big transformation into a spa town, it needed willing individuals who put their lives into trying to make their town the best spa town around. If it weren't for these people, springs wouldn't have been found, so baths couldn't have been

  1. Absorption Spectrum of Chlorophyll.

    Micropipette 12. 100 ml measuring cylinder 13. Aluminum foil 1. Milton Roy Spectronic 20D Spectrophotometer ( range: 400-700 nm, wavelength accuracy = ? 3 nm, absorbance accuracy = 0.5 percent transmittance) 2. Lab View (Interface designed by Al Giandomenico)

  2. The aim of this science investigation is to find out where the stomata are ...

    If you attach a perometer to a leaf and take measurements of its resistance to airflow at intervals, you will find that there is a generally less resistance during daylight hours than at night. This is because the stomata open during the day and close at night.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work