After all this info you have given me, the correct one is Keystone species. As defined in sources like National Geographic, <span> These are types of plants or animals that play a unique and crucial role in the way an ecosystem functions. Without </span>keystone species<span>, the ecosystem would be dramatically different or cease to exist altogether. I hope this helps you a lot </span>
I believe the lowest orange square would
There are choices for this question namely:
<span>A) B cells produce IgE antibodies
B) B cells release cytokines
C) cytotoxic T cells present the class II MHC molecule-antigen complex on their surface
D) helper T cells release cytokines
The correct answer is "helper T cells release cytokines". Cytokines are released by helper T cells when B cells attach to them via receptors. These T cells "help" these B cells to differentiate by secreting certain cytokines. When B cells differentiate, they are converted to plasma cells and able to secrete antibodies to the antigen presented to the T cells. </span>
They concluded that horses evolved with the emergence of grasslands and an increase of predators. The digits of their early Eocene ancestor evolved into hooves.
Answer:
Nutrient-rich blood flows into the liver from the intestines through the hepatic portal vein.