Alveoli
bones are hard, cartilage are soft and bendable , eg your ear, nose..
Neurotransmitters can directly or indirectly affect behavior. It influences neurons in a specific portion of the brain. Any abnormal level in neurotransmitters can lead to mental disorders.
It burns.
Skeletal muscles.
Nervous tissue.
skeletal muscle tissue
Homeostasis is the process in a system that maintains internal balance and stability.
It is called osteoporosis (bones with many holes).