Answer:
The nervous system and the endocrine system are both necessary to maintain homeostasis and keep the human body alive.
There are options for this question they are:
a) neutral stimulus; conditioned stimulus
b) conditioned stimulus; neutral stimulus
c) unconditioned stimulus; conditioned stimulus
d) neutral stimulus; unconditioned stimulus
e) unconditioned stimulus; neutral stimulus
The correct answers are - In this example, the buzzer begins as the neutral stimulus and eventually becomes the conditioned stimulus. The buzzer initially is a neutral stimulus because it have no role to play in the blinking response. Eventually though through learned association the buzzer becomes a conditioned stimulus because you now associate it with a puff of air to the eye which in turn causes you to blink.
<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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Answer:
Ionizing radiation comes from these main sources:
Nuclear reactions in the Earth's sun and stars in space.
Radioactive decay in the body's tissues and in the soil.
Radioactive decay of unstable elements in rocks, especially rocks that contain radium and release radon gas.
Other examples of ionizing radiation include alpha, beta, and gamma rays from radioactive decay.
Answer:
Natural selection is the process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin and is now believed to be the main process that brings about evolution while Artificial selection is Selective breeding is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits by choosing which typically animal or plant males and females will sexually reproduce and have offspring together.
