Search results
Results from the WOW.Com Content Network
Spongy tissue is a type of tissue found both in plants and animals. In plants, it is part of the mesophyll , where it forms a layer next to the palisade cells in the leaf . The spongy mesophyll's function is to allow for the interchange of gases (CO 2 ) that are needed for photosynthesis .
Palisade cells are located beneath the upper epidermis and cuticle but above the spongy mesophyll cells. Palisade cells contain a high concentration of chloroplasts , particularly in the upper portion of the cell, making them the primary site of photosynthesis in the leaves of plants that contain them.
The spongy mesophyll cells are loosely packed, allowing for an increased surface area, and consequently an increased rate of gas-exchange. Uptake of carbon dioxide necessarily results in some loss of water vapor, [ 38 ] because both molecules enter and leave by the same stomata, so plants experience a gas exchange dilemma: gaining enough CO
The pores or stomata of the epidermis open into substomatal chambers, which are connected to the intercellular air spaces between the spongy and palisade mesophyll cell, so that oxygen, carbon dioxide and water vapor can diffuse into and out of the leaf and access the mesophyll cells during respiration, photosynthesis and transpiration.
In leaves, the vascular bundles are located among the spongy mesophyll. The xylem is oriented toward the adaxial surface of the leaf (usually the upper side), and phloem is oriented toward the abaxial surface of the leaf.
Peter Navarro, senior trade adviser to U.S. President Donald Trump, said Mexico had been "very cooperative" on efforts to crack down on the influx of fentanyl into the U.S., and Canada had started ...
English: The fine scale structure of a leaf featuring the major tissues; the upper and lower epithelia (and associated cuticles), the palisade and spongy mesophyll and the guard cells of the stoma. Vascular tissue (veins) is not shown.
The BBC has contacted Dr Carpenter for comment. In a statement, the Abortion Coalition for Telemedicine, which Dr Carpenter co-founded, called the indictment against her "the latest in a series of ...