Answer:
A pollen tube grows from the pollen grain into the ovary
Explanation:
Water is needed for fertilization in several plant groups because the sperm needs to swim to meet the non-motile eggs of the female organs.
<em>However in angiosperms, the pollen germinates and a structure known as pollen tube which contains the male gametophyte (sperm) grows into the ovary where the ovule is located and the male gametophyte is deposited in the ovule to initiate the fertilization process.</em>
<em>Hence, water is really not necessary for fertilization in the angiosperms.</em>
Answer:
The secondary immune response is the immune response when the same antigen , memory cells that was encountered before is remembered and the immune system make antibodies to counter it.
Explanation:
There is a difference between the primary immune response and secondary immune response.
In the primary immune response occur when the immune system encountered an antigen for the first time which lead to the generation of memory cells and and the B cells with the T cells produce antibodies.
While the secondary immune response occur when the same antigen that was encountered the first time is encountered the second time and it lead to the stimulation of memory cells to produce more and high quantities of antibodies to fight foreign substances.
Answer:
in the west hope this helps
Explanation:
Answer:
D.
Explanation:
It is all of these because the motion is A. speed because when something is moving it has a certain speed. B. position. it's motion determines its next position. direction because without direction it would not move. direction DIRECTS it which way to go. so D. , all of them
1. Sunlight warms the surface and water evaporates.
2. Warm, moist layer builds up between 1000 and 5000 feet.
3. Rising air currents organize into “thermals”
4. Water vapor in rising air parcels condenses to form clouds.
