Answer:
I had a step stool with a shed in a web that looks exactly like this and my dad said it was a black widow shed so idk maybe you should look up black widow sheds because I can't find any.
Explanation:
In the block to polyspermy, entry of the sperm's contents causes calcium ion levels in the oocyte's cytoplasm to rise, triggering the cortical reaction.
In biology, polyspermy describes the fertilization of an egg by more than one sperm. Diploid organisms normally contain two copies of each chromosome, one from each parent.
The cell resulting from polyspermy, on the other hand, contains three or more copies of each chromosome—one from the egg and one each from multiple sperm. Usually, the result is an unviable zygote. This may occur because sperm are too efficient at reaching and fertilizing eggs due to the selective pressures of sperm competition.
The cortical reaction is a calcium-dependent exocytotic process in which the content of secretory granules is released into the perivitellin space immediately after fertilization, which serves to prevent polyspermic fertilization.
Learn more about polyspermy here : brainly.com/question/4537960
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A.
<u>The ribcage expands to allow air to enter the lungs</u> is an example of the skeletal system interacting directly with the respiratory system.
Explanation:
The skeletal system is mainly made up of bones - like the ribcage in this case - while the respiratory system is made up of the lungs, trachea, diaphragm, etc.
When inhaling, the diaphragm contracts, therefore increasing the volume of the chest cavity. The muscles between the ribs also contract causing the ribcage to stretch upwards and outwards. This also contributes to an increase in the volume of chest cavity. Consequently, the pressure in the chest, decreases causing atmospheric pressure to rush air into the lungs.
When these muscles contract, they raise the pressure in the chest cavity causing air to rush out of the lungs.
Learn More:
For more on interaction of the skeletal system and the respiratory system check out;
brainly.com/question/13947489
brainly.com/question/2756469
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<span>Nasal insufflation, also commonly referred to as snorting, is the inhalation of a crushed or powdered substance through the nose. It leads to a number of problems including perforation of the nasal septum, irritation of the nasal cavity, nose bleeds, and loss of smell.</span>
Prokaryotic cells are simple orgamisms. this includes bacteria, they also do not have a nucleus. I also imagine that they are in the same kingdom because they are both cell, but im not completely sure
