This might have been the cause of not being exposed to this specific pollen during his years in Chicago. Allergic reactions can develop when the stimuli presented even when its not contagious causes the immune system to trigger and act in a defensive stance. This delayed effect may have been the cause of the sudden expression of the immune system.
I originally asked for the images but I will give it my best shot at answering your question without them! :D
There are only three types of plant tissues:
1. Dermal
2. Ground
3. Vascular
The dermal tissue is the outside of the plant's root, stem, or leaf, A.K.A the the skin. If you're looking at a circular image, what ever is pointing to the outside ring of the stem is the dermal tissue.
The ground tissue is the flesh of the plant that is inside the dermal tissue. It surrounds the vascular tissue in the middle of the stem. Whatever letter is pointing to the wide, fleshy ring, that is touching the dermal tissue is the ground tissue. It is the largest part of a plants stem, roots, or leaves.
Lastly, the very inner ring or rings of the plant is the vascular tissue. It's made up of xylem and phloem. This can be found in many different places depending on the part of the plant, but what you're looking for is tiny circles within the ground tissue. If you're looking at the roots, you will see one circle in the very center of the plant, surrounded by ground tissue. If you're looking at the leaves, you will see one circle as well, and additionally other tiny circles throughout the ground tissue in each wing. Lastly, if you're looking at the stem, you'll see a circle of tiny circles within the ground tissue. These small circles are all vascular tissue.
Alfred Wegener found some evidence and these are some examples:The Appalachian Mountains start in North America and it is connected along the European coastline. This tells us that once the continents were connected,and,The continents fit together like a puzzle.Also some of the fossils are found around the borderlines
hope this helps man and could i please get brainliest
:D
What brought the most benefits to humanity was probably the discovery of DNA. The history of biology came to be from Egyptian methods of medicines and native traditions.
The answer is Stimulus Discrimination.