what is the name of structure F?

What is the name of structure F? 

Which of the following is/are true regarding the cardiac stomach? 

What is structure A in the circulatory system?

Sea stars, and all echinoderms have a(n) 

What is the name of the structure at B?

Increased humidity and temperature are often correlated with higher biodiversity. In turn, higher biodiversity is correlated with which of the following? 

Pleopods are also referred to as 

What is structure B called? 

What is the function of the pyloric ceca?