Answer:
You have external defense systems, which include your skin, tears, mucus, saliva, stomach acid, cilia (small hairs) and helpful bacteria. The skin, nails and hair form the integumentary system, which stops dirt and pathogens from entering the body.
Glacier because ice sheet and stuff and science ill explain more in the comments
Answer:
Littering and Destroying things. This affects the environment because animals could get ahold of the trash and you could me destroying their homes.
Explanation: