Earth’s global temperature has changed greatly in the past hundreds of years. This is due to how much energy the planet is receiving from the sun and how it radiates back. Another cause is humans, due to deforestation, burning of fossil fuels, pollution, etc.
The lower invertebrate phylum that has the greatest diversity is called Arthropod. An Arthropod is an invertebrate animal that has a segmented body, an exoskeleton, and paired jointed appendages. Arthropods include an incredibly diverse group from the phylum Euarthropoda, which includes myriapods, <span>arachnids, insects, and crustaceans.</span>
<h2>Xylem;phloem and cork</h2>
Explanation:
Wood is mainly known as secondary xylem found in trees
- Xylem is basically the vascular tissue which is responsible for the conduction of water and nutrients from the roots to shoots and leaves
- Secondary xylem is formed from secondary growth and is associated with lateral growth and grows from the vascular cambium
- Its cell walls are thickened by deposition of lignin which provides mechanical support to plants and consists of tracheids and vessels that are shorter and wider
- In large woody plants secondary xylem get differentiated into heartwood and sapwood
Bark is essentially made of phloem and cork
- Bark sole purpose is to provide protection to trees
- The inner bark is produced by vascular cambium which consists of secondary phloem whose innermost layer transports food from the leaves to rest of the plant
- The outer bark is a dead tissue which is the product of cork cambium
