Hey. The first sound is the "lub." This is what you hear once the mitral and tricuspid valves of the heart close, which are the valves between the atria and the ventricles! Super cool. It is your third answer choice.
Answer:
Homologous structures are structures that are similar in related organisms because they were inherited from a common ancestor. These structures may or may not have the same function in the descendants.
My answer uh might not be the one you're looking for or isn't correct ✌
Explanation:
Explanation:
direct channel allows the consumer to make purchases from the manufacturer while an indirect channel allows the consumer to buy the goods from a wholesaler or retailer. Indirect channels are typical for goods that are sold in traditional brick-and-mortar stores.
Answer:
Oviparous
Explanation:
The most common reproductive strategy in marine ecosystems is oviparity. 43% of cartilaginous fish are oviparous.
Explanation:
HIV attacks a specific type of immune system cell in the body. It's known as the CD4 helper cell or T cell. When HIV destroys this cell, it becomes harder for the body to fight off other infections. When HIV is left untreated, even a minor infection such as a cold can be much more severe.
