Intro to Animal Organization and Physiology Flashcards
From smallest to largest, what are the 5 levels of organization in the human body?
Cells, tissue, organs, organ system, and organism
All cells arise from division of ____ cells.
Preexisting
What two general classes of cells does the human body contain?
Somatic or body cells and Germ or reproductive cells: sperm and eggs
What is a somatic cell?
Body cells
What is a germ cell?
Reproductive cells: sperm and eggs
To work efficiently, several different types of cells must _____ their efforts.
coordinate
Provide the definition of a tissue:
Collection of specialized cells and cell products that carry out a limited number of function
When are tissues formed?
When the same type of cells act together in a function.
Define what an organ is?
Collection of tissues working together to perform a function. Eg. lungs, liver, stomach, intestines, kidneys.
Do the functions of organ systems share significant overlap?
Yes, eg. the nervous system and the endocrine system both operate via a shared organ: the hypothalamus.
What constitutes an organ system?
Two or more organs working together in the execution of a specific body function. Eg. Digestive system, cardiovascular system, nervous system, etc.
Describe the levels of organization in a multicellular organism? provide examples for all.
Chemical level: a molecule in the membrane that encloses the cell.
Cellular level: a cell in the stomach lining.
Tissue level: layers of tissue in the stomach wall
Organ level: The stomach
Organ/body system: Digestive system
Organism: the whole body
What are the two classifications of organisms based on the number of cell?
Unicellular organisms- single cells eg. bacteria
Multicellular organisms- many cells eg. humans, animals
What is functions are a distinction of multicellular organisms?
have complex bodies as it performs multitude functions such as respiration, digestion, movement, and blood circulation.
All life on earth began as a single cell. T/F
True. These single cells were able to survive on their own for billions of years before aggregating together to form multiple groups.
The evolution of multicellularity is a major transition in ______.
Individuality, from autonomously replicating cells to groups of interdependent cells forming higher levels of organization.- evolution of life.
Why did the transition into multicellular life begin?
evolution of cooperation, where cells unite together and gain an advantage over solitary cells
What is one driving factor mentioned for evolving multicellularity?
predation