Answer:
Friction: A force that opposes the motion of objects that touch as they move past each other. Friction acts at the surface where objects are in contact.
Explanation:
The force that acts against your pushing force is called friction. is a force that resists the motion between two surfaces in contact. When you try to slide two surfaces across each other, the force of friction resists the sliding motion.
Answer:
I think the electron microscope can magnify objects up to 200,000 times.
Explanation:
Answer:
That's correct most birds have diffrent shaped beaks for diffrent reasons for example some birds can tweezer beaks which helps to dig into the worm holes to get worms or help to drill into trees
Explanation:
The student who caught the cold caused by this specific Rhinovirus was exposed to the exact same Rhinovirus 18 months later. Memory B cells of the immune system will protect her from getting the same cold again.
In immunology, a memory B cell (MBC) is a type of B lymphocyte that forms part of the adaptive immune system. These cells develop within germinal centres of the secondary lymphoid organs.
Memory B cells circulate in the blood stream in a quiescent state, sometimes for decades. Their function is to memorize the characteristics of the antigen that activated their parent B cell during initial infection such that if the memory B cell later encounters the same antigen, it triggers an accelerated and robust secondary immune response.
Memory B cells have B cell receptors (BCRs) on their cell membrane, identical to the one on their parent cell, that allow them to recognize antigen and mount a specific antibody response.
Learn more about memory B cell here : brainly.com/question/23423029
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I think the correct answer would be A. The yolk sac becomes the placenta. It is membranous sac that is attached to the embryo. It provides all the nutrition and the blood cells needed by the embryo. It is also called the umbilical vesicle.