unit 2 parts of the cell Flashcards
Serves as an external cell barrier and acts in transport of substances into or out of the cell. maintains an electrical condition that is essential for functioning excitable cells. External facing proteins act as receptors (for hormones, neurotransmitters, and so on) , transport proteins, and in cell-to-cell recognition.
Plasma membrane
Membrane made of double layer of lipids (phospholipids, cholesterol, and so on) with proteins embedded within. most externally facing proteins and some lipids have attached sugar groups.
Plasma membrane
cellular region between the nuclear and plasma membranes. Consists of fluid cytosol containing dissolved solutes, organelles ( the metabolic machinery of the cytoplasm), and inclusions (stored nutrients, secretory products, pigment granules).
cytoplasm
site of aerobic respiration ( the “burning” of glucose) and ATP synthesis; powerhouse of the cell.
mitochondria
Rodlike, double-membrane structures; inner membrane folded into projections called cristae.
mitochondria
the sites of protein synthesis
Ribosomes
Dense particles consisting of two subunits, each composed of ribosomal RNA and protein. Free or attached to rough endoplasmic reticulum.
Ribosomes
membrane network studded with ribosomes
rough endoplasmic reticulum
Synthesizes steroid hormones
smooth endoplasmic reticulum
assembles and packages materials in vesicles to be secreted from the cell
Golgi apparatus
forms the mitotic spindle and the base of the cilia
centrioles
site of ribosome synthesis
nucleolus
contains the cell contents and separates them from the surrounding environment
plasma membrane
control center of the cell
nucleus
energy-generating powerhouse of the cell
mitochondria
sac of digestive enzymes
lysosomes
the enzymes detoxify a number of toxic substances such as free radicals. the most important enzyme, catalase, breaks down hydrogen peroxide.
peroxisomes
sugar groups are attached to proteins within tunnels. proteins are bound in vesicles for transport to the golgi apparatus and other sites. External face synthesizes phospholipids.
rough endoplasmic reticulum
support the cell and give it shape. Involved in intercellular and cellular movements. form centrioles and cilia and flagella, if present
microtubules
involved in muscle contraction and other types of intercellular movement; help form the cell cytoskeleton and microvilli, if present.
microfilaments
the stable cytoskeleton elements; resist mechanical forces acting on the cell
intermediate filaments
separates the nucleoplasm form the cytoplasm and regulates the passage of substances to and from the nucleus.
nuclear envelope
DNA constitutes the genes, which carry instructions for building proteins.
Chromatin
