cells - chapter 2.1 - 2.3 Flashcards
(25 cards)
What is the smallest structure that can perform life’s functions?
A cell
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 separates the nucleus from the cytoplasm?
A nuclear membrane (double membrane).
What is contained within the nucleus?
DNA, which contains inherited information.
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 of the Golgi body?
Modifies proteins and packages them for secretion from the cell.
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.
What is the shape of mitochondria?
Spherical or sausage-shaped structures.
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.
Fill in the blank: The cytoskeleton consists of microtubules and _______.
microfilaments.
