Males have XY and females have XX
Answer:
Primary succession is one type of the ecological succession which takes place on the land devoid of vegetation or barren land.
The species which first flourishes on this barren land are known as pioneer species which includes the species of bryophytes and pteridophytes like lichens and mosses.
These lichens and mosses help breakdown the barren rocks through chemical leaching and help increase the nutrient content. This allows the ferns and small pteridophytes to grow.
Then the area is colonized by the intermediate species which includes herbs, shrubs later trees. These intermediate species help attract the animals and thus help establish the biological community.
Thus, Lichens mosses → herbs→ shrubs →trees.
George is lifting weights. He starts by doing biceps curls
which involves flexing his
elbows. His elbow is able to bend
because the humero-ulnar joint is a hinge
joint. Sam is doing leg presses, extending his knees as he pushes
against the weights. Meanwhile, Jane is doing "lat pulls" by pulling
downward on a weighted bar. This movement involves adduction of her arms.
Her shoulder joint is a ball-and-socket joint, allowing
a wide range of movements.
