Because they are prokaryotic cells.
<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
Answer:
Consequences of the widespread use of plastic materials can be an increase in levels pollution and the overflowing of landfills because most plastics are non-biodegradable and can take a very long time to disappear unlike things like paper which are biodegradable.
Research indicates that stress can produce direct physiological effects such as elevated blood pressure, increased hormonal activity, and decrease in immune system functioning. Or, in other words, all except psychological disorders.
Answer:
We ruin the ecosystem with pollution, littering, habitat destruction, and extinction of the wildlife.
Arruinamos el ecosistema con la contaminación, la basura, la destrucción del hábitat y la extinción de la vida silvestre.