HIV in fact kills the immune system cells causing our body cannot fight off infections and diseases from entering our body. this creates our immune system to become weaken.
Answer:
B. often use tube feet to move around in their environment
Explanation:
Tube feet are tiny tubular projections of echinoderms on the underside (oral side). They are a member of the echinoderm water vascular system.
Tubular feet are used for feeding, breathing and shifting. They are arranged around the sides, in grooves. They work by hydraulic pressure. They are used to transfer food in the centre to the oral mouth, and may stick to surfaces. Tube feet allow certain animals to stick and travel slowly to the ocean floor. for example starfish uses tube feet for the above functions.
Hence, the correct option is B.
14. compound
15. the concentration cannot be increased.
16. heterogenous mixtures
17. chocolate chip cookies
18. vegetable soup
19. a mixture is a pure substance a compound is not
20. Tastes sour