Chapter 1 Flashcards
The human body has many levels of structural organization. What is the simplest level of the structural hierarchy?
the chemical level. Atoms combine to form molecules such as water and proteins.
What is the second level of hierarchy?
the cellular level. cells are the smallest units of living things. They vary widely in size of shape reflecting their unique function in the human body
What is the third level of hierarchy?
the tissue level. Tissues are groups of similar cells that have a common function.
What are the 4 basic types of tissue in the human body?
epithelium, muscle, connective and nervous tissue
What is a discrete structure composed of at least two tissue types?
An organ. (4 types of tissue is more common) Think of each organ as a specialized functional center responsible for a necessary activity that no other organ can perform.
After the organ level, what is the next level of organization?
The organ system level. Organs that work together to accomplish a common purpose make up an organ system.
Ex. The heart and blood vessels of the cardiovascular system.
How many organ systems are there?
11.
What is the highest level of organization?
The organism. The living human being. The organismal level represents the sum total of all structural levels working together to keep us alive.
What cannot be emphasized TOO STRONGLY?
ALL BODY CELLS ARE INTERDEPENDENT (dependent on each other). Humans are multicellular organisms and our vital body functions are parceled out among different organ systems. Organ systems work cooperatively to promote the well-being of the entire body.
What are the necessary life functions?
Maintaining boundaries, Movement, Responsiveness, Digestion, Metabolism, Excretion, Reproduction and Growth.
State of body equilibrium or stable internal environment of the body?
Homeostasis. Literal translation is “unchanging” but actually is a dynamic state of equilibrium where internal conditions vary but always within narrow limits. In general, the body is n homeostasis when its needs are adequately meant and it’s functioning smoothly.
Communication within the body is accomplished chiefly by what systems?
the nervous and endocrine systems.
Most homeostatic control mechanisms are?
negative feedback mechanisms. (think of a thermostat)
The ventral body cavity houses internal organs. It’s collectively called?
Viscera
