cells Flashcards
(27 cards)
describe cells
the smallest structure that can perform life’s functions, Cells vary in size and shape, but all
human cells have a similar basic
structure.
The cell is considered the basic unit of life.
What does the cell theory state?
All organisms are made of cells, which are the basic unit of life and arise from pre-existing cells.
What is the role of the cell membrane?
Separates the cell contents from the environment and controls entry and exit of substances.
What are organelles?
Structures inside the cell formed by internal membranes.
What is cytoplasm?
Jelly-like material filling the space between the nucleus and the cell membrane.
What is the composition of cytosol?
75% to 90% water with dissolved substances such as salts and carbohydrates.
Where do most metabolic reactions occur in the cell?
In the cytosol.
What is the largest organelle in the cell?
The nucleus.
what is a nuclear membrane (double membrane).
membrane that separates the nucleus from the cytoplasm, Nuclear pores in the nuclear membrane allow large
molecules, such as messenger RNA, to enter and
leave the nucleus.
What is contained within the nucleus?
DNA, which contains inherited information. and the nucleolus that plays a part in manufacturing proteins.
What is the function of ribosomes?
Join amino acids together to make proteins.
What are the two types of endoplasmic reticulum?
Rough ER (with ribosomes) and smooth ER (without ribosomes).
What is the function and structure of the Golgi body?
a series of flattened membranes stacked one upon the other, usually positioned near the nucleus. Modifies proteins and packages them for secretion from the cell.
Proteins produced at the ribosomes pass through the channels of the endoplasmic reticulum to the Golgi body. At the edges of the membranes of the Golgi body, small sacs of liquid containing proteins are formed.
What are vesicles?
Small sacs of liquid containing proteins formed at the edges of the Golgi body.
What do lysosomes contain?
Digestive enzymes that break down large molecules. when particles or liquids are taken into a cell they form vesicles in the cytoplasm, lysosomes can join with the vesicles to break down the contents of the vesiscles.
What is the structure of mitochondria?
Spherical or sausage-shaped structures. has a double membrane. The smooth outer membrane surrounds the mitochondrion,
while the inner membrane, called the
cristae, is arranged into a series of folds
that extend into the interior of the
organelle.
What occurs in mitochondria?
Some chemical reactions of cellular respiration.
What is the function of cilia?
Beat back and forth to move the whole cell or substances over the surface.
What is a flagellum?
A long projection used for movement, usually one or two per cell.
What is the cytoskeleton?
A framework of protein fibers that gives the cell its shape and assists in movement.
What are microtubules?
Hollow rods that keep organelles in place or move them around the cell.
What are centrosomes?
Structures consisting of two perpendicular centrioles made of microtubules.
What are inclusions?
Chemical substances found in the cytoplasm that are not part of the cell structure.
microfilaments
move materials around the cytoplasm or move the whole cell.
