They drop on the ground and the wind blows them or birds pick them up and drop them or bees
Answer:
Option c (No, T cells left from the previous infection can kill any virus.
)
Explanation:
When ever viral infection occur, body's immune system start to fight against it by activating B-cells and T-cells.
B-cells produce antibodies that bind with virus and act as label. This label indicate virus as foreign substance. Hence T-cells recognize it and kill it. Furthermore, B-cells form memory cell that keep the viral memory. if this viral infection occur again in future, T-cell recognize it and eliminate the virus.This mechanism is called immunity.
Answer: Glial cells called ASTROCYTES help maintain the blood-brain barrier, whereas SCHWANN CELLS create the myelin that envelopes axons
Explanation: Glial cells are specialized cell that are found in both central and peripheral nervous systems, that surrounds the neurones, providing them with support and insulation. There are different types of Glial cells these includes:
- Astrocytes: they maintain the blood brain barrier.
- Schwann cells: create the myelin that envelopes axons of the peripheral nervous system neurones.
- satellite cells: These cells help regulate the external chemical environment of neurones.
- Microglia: they clean up cellular debris through phagocytosis.
- Oligodendrocytes: create the myelin that envelopes axons of the central nervous system
Marmots is a primary consumer
Mosses are producers
Lynx is predator
Dung cannon is decomposers