What is the difference between the density of stomata on the lower surface of the leaf and on the upper surface of the leaf?

Explanation: All surfaces of the leaf have some amount of stomata for regulating gas exchange for photosynthesis. However, the lower epidermis (the underside of the leaf) has more, because it is more often in the shade and so it is cooler, which means evaporation won’t take place as much.

Which has more stomata Adaxial or Abaxial?

The stomatal control of diffusion through leaf surfaces depends on both the densities and dimensions of stomata. In general, stomatal densities are higher in the abaxial than in the adaxial epidermis of most species, except in the Graminae where there are more or less equal densities on both surfaces.

Why does stomatal density differ for different species?

Variation in size and density of stomata may arise due to genetic factors and/or growth under different environmental conditions.

How does density of stomata vary?

A change in stomatal density modifies the number of sites available for gas exchange per unit leaf area, and an increase in stomatal size decreases gas diffusion rate by increasing the length of the diffusion pathway.

How does the density of stomata vary amongst leaf surfaces?

The number of stomata on leaf surfaces varies widely among different species of plants. The lower epidermis of the leaf tends to have a higher total than the upper surface. The average number of stomata is about 300 per square mm of leaf surface.

Is there a difference in the stomatal indices of the upper and lower side surface of the dicot and monocot leaves?

Usually the lower surface of a dicot leaf has a greater number of stomata while in a monocot leaf they are more or less equal on both surfaces. In most of the floating plants, stomata are found only on the upper epidermis.

Does the density of stomata differ between the adaxial epidermis and abaxial epidermis of a leaf organ?

First, stomatal density is usually higher on the abaxial surface than it is on the adaxial surface of leaves (Willmer and Fricker, 1996a).

What is the difference between abaxial and adaxial?

The adaxial and abaxial epidermal cells have different complexities and different cuticular thicknesses. The adaxial palisade mesophyll cells are oblong in shape, densely packed and contact with each other, while the abaxial spongy mesophyll cells are uneven in shape and have air spaces between them.

What does a higher stomatal density mean?

The more stomata per unit area (stomata density) the more CO2 can be taken up, and the more water can be released. Thus, higher stomata density can greatly amplify the potential for behavioral control over water loss rate and CO2 uptake.

Why do shorter trees have higher stomatal density?

Higher densities of small stomata lead to increases in stomatal conductance to water vapor over the same total pore area, due to the shorter diffusion path length (45) . … In addition, greater stomatal density was observed in genotypes with resistance to water stress [60,63].

What determines stomata density?

Stomatal density (SD) is a function of both the number of stomata plus the size of the epidermal cells. Thus, SD is affected both by the initiation of stomata and the expansion of epidermal cells.

What is stomata density?

What is the difference between a stoma and anisocytic stomata?

A Stoma is not surrounded by a definite number or arrangement of cells; it appears to be embedded in the epidermal cells. An Anisocytic Stomata is surrounded by three lopsided subsidiary cells, where one is distinctly smaller than the other two; Anisocytic stomata is also known as cruciferous or unequal celled type stomata.

What is an anomocytic stoma?

Anomocytic (also called ranunculaceous or irregular-celled type): Anomocytic stoma remains surrounded by cells that are not different from other epidermal cells so far as size and shape are concerned. There exist no definite number and arrangement of cells that surround a stoma. A stoma appears to be embedded in epidermal cells.

Do all grasses have anomocytic stomata?

Most of the 108 monocotyledonous species have paracytic or tetracytic stomata, but some species in Alismatales, Dioscoreales, Liliales, and Asparagales have anomocytic stomatal type (Supplementary Table S1). Does Molecular and Structural Evolution Shape the Speedy Grass Stomata?

Is Dactylorhiza umbrosa stomatal anomocytic?

The stomatal type is anomocytic. Occasionally stomata observed unpaired guard cells as well as result in stomatal twinning. Average Guard cell lengths vary between 33.47-63.96 μm for adaxial surfaces and 67.4 μm for abaxial surfaces. The presence of calcium oxalate raphides occur in Dactylorhiza umbrosa.