Where are large number of chloroplast found in the plant?
What structure on a leaf contains the most chloroplasts?
Palisade mesophyll layer
How many chloroplasts does a leaf have?
A cell from a leaf may contain from 20 to 100 chloroplasts (Figure 1). The shape of chloroplasts is variable, from round to ellipsoid, or much more complex. Chloroplasts are members of the plastids family and contain DNA with around 250 genes derived from the prokaryotic bacterial ancestor.
What part of the leaf does the light hit?
Light absorption happens in the palisade mesophyll tissue of the leaf. Palisade cells are column shaped and packed with many chloroplasts . They are arranged closely together so that a lot of light energy can be absorbed.
What controls the opening and closing of stomatal pores and how?
The opening and closing of stomata are controlled by the guard cells. When water flows into the guard cells, they swell up and the curved surface causes the stomata to open. When the guard cells lose water, they shrink and become flaccid and straight thus closing the stomata.
Why do guard cells look darker in the leaf section?
Answer: the guard cells appear darker in colour due to the presence of chlorophyll and thicker wall in them.
What is the function of guard cells in a leaf?
Guard cells optimise leaf gas exchange in response to changing environmental conditions and their turgor is controlled by alterations in atmospheric CO2 concentration, light intensity, humidity and the drought hormone abscisic acid.
Where is the epidermis of a leaf located?
The outermost layer of the leaf is the epidermis. It consists of the upper and lower epidermis, which are present on either side of the leaf. Botanists call the upper side the adaxial surface (or adaxis) and the lower side the abaxial surface (or abaxis). The epidermis aids in the regulation of gas exchange.