Lecture 1- Introduction to bio and life, forms of life, cell theory Flashcards
what is biology
they study of life
word biology is formed by combining the greek “bios” meaning life, and the suffix logy meaning science of, study of
various forms of life exist in the form of…
organisms
what is an organism
from term “orginization” and brodly defined as an assembly of molecules functioning as a stable whole that exhibits life
what is a unicellular organism
also known as a single cell organism its a living form that consists of one cell
ie. unicellular bacterium
what is a multicellular organism
tissue, organ or organism that is made up of many cells is said to be multicellular
ie. multicellular tissue in human (connective tissue, epithlial tissue, muscle tissue, nervous tissue)
what is a cell
the basic structural and functional unit of all living organisms
what are the main tenets if modern cell theory that science supports
-all organisms are composed for one or more cells
-if cells are broken, the property of life is lost
how big are cells
they are small. usually ranging from about 1 to 100 micrometers in diameter
how many cells would a pint of blood have in it
over 5 billion cells
what is the collective term for mitosis and meiosis
cytokinesis
what is mitosis
the process in which a eukaryotic cell nucleus splits in two, followed by division of the parent cell into two daughter cells
what is meiosis
a type of cell division in sexually reproducing organisms that reduces the number of chromosomes in gametes
what kinds of cells are not small
eggs
what happens if a cell breaks down
being small they can easily be repaired or discarded
are specialized cells easy to replace
yes they can easily be replaced with out disruption of a function
what is a cell a living form of
a living globule of cytoplasm
what is the cytoplasm
the gelatinous liquid that fills the inside of a cell
what is the cytoplasm composed of
waters, salts, and various organic molecules
how many reactions happen in the cell
a vast number of reactions are taking place millions of times per second
how do cells move molecules into the cell
simple diffustion
how does the length of travel effect how fast something travels
very rapid over a short distances but slower over long distances
what is a capillary
a small blood vessel
how big are capillaries
around 5 to 10 micrometers
how thick is a capillary
one endothelial cell thick
what happens to the cells volume to surface area ratio as when you increase the size of the cell
as the size of the cell increases the ratio gets smaller
ie. as the cell gets bigger the volume size increases much faster then the SA
is there a limit to the size a cell can get
yes. cells cant increase beyond certain limits
why cant cells get bigger beyond a limit
by cells increasing internal volume less and less surface area is available to exchange materials needed by the cell
