What is the first section of the small intestine ?
duodenum
What structure controls simple reflexes ?
spinal cord
through what process does water in the soil enter a root's hairs ?
osmosis
The brain and the spinal cord are part of the _________ nervous system.
central
urinary system
What is the scientific name for the windpipe ?
trachea
What portion of the body contains most of the vital organs ?
trunk
What plant tissues carry food downward to the stems and roots ?
phloem
What is a sensible explanation to a scientific problem ?
hypothesis
Which body system provides movement for the body ?
muscular system
The spleen is the largest ________ _________.
lymphatic organ
What gland is considered the " master gland " ?
pituitary gland
What type of leaf has only one blade attached to the petiole ?
simple leaf
Muscles that work without thinking about it are called __________ muscles.
Which body system supports the body and protects vital organs ?
skeletal system
Which dome-shaped organ aids in breathing ?
diaphragm
What structure connects bones to muscles ?
tendon
Which branch of biology studies the relationships between organisms in their environments ?
ecology
The main divisions of the skeleton are the axial skeleton and the _____________ skeleton.
appendicular
Which body system transports nutrients and oxygen to cells and carries wastes from cells ?
cardiovascular system
The gallbladder stores what ?
bile
What are the air sacs in the lungs called ?
alveoli
fruit
Blood enters the heart through the upper chambers, which are called _____________.
atria
Which body system controls other body systems ?
nervous system