PLEASE NEED CORRECT ANSWERS ASAP 40 POINTS Gastric juices are secreted by glands which are located in the .

small intestine
mouth
stomach
pancreas

Match these items.

1. absorbs most ultraviolet rays

stratosphere
2. lowest layer of the atmosphere

greenhouse effect
3. starts seven miles above the earth

thermosphere
4. layer composed of layers

troposphere
5. important for its radiowave reflection

ozonosphere
6. trapping of heat by earth's atmosphere

ionosphere

Which of the following is not a symptom of desertification? a) decrease in salt content of the soil b) lowering of the water table c) reduced surface water d) increased soil erosion e) loss of native vegetation

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons