Involuntary action in body
When you spin around, you lose balance because of fluid spinning around in the C) semicircular canals.
Atria is a large part of the heart so too big for cells; arteries & veins lead away or to the heart.
Capillaries are the smallest vascular structures that allow materials to be exchanged easily between cells.
Answer:
Which of the following mechanisms is used by gram-negative bacteria to cross the blood-brain barrier? D) Inducing TNF
Explanation:
The blood brain barrier is a barrier formed by brain microvascular endothelial cells, astrocytes and pericytes. Pathogens can cross this barrier by using different mechanisms. The Tumor Necrosis Factor (TNF) is the way gram-negative bacteria cross this mentioned blood-brain barrier.
Protects the growing tip of the plant