lecture 6 Flashcards
cellular component summary:
extracellular matrix: surrounds cells, providing biochemical and structural support. only in eukaryotic plants. cilia: move the cell through fluid or move fluid past the cell surface. only present in animal cells. flagella: move the cell through fluid. present in prokaryotes and animals. Plasma membrane: isolates the cell contents from the environment, regulates movement of materials into and out of the cell, allows communication with other cells. present in all cells. Genetic materials: encodes the information needed to construct the cell and to control cellular activity. Present in DNA. chromosomes: contain and control the use of DNA. single circular in prokaryotes, many linear in plants and animals. Nucleus: contains chromosomes and nucleoli. present in plants and animals. nuclear envelope: encloses the nucleus, regulates movement of materials into and out of the nucleus. present in plants and animals. Nucleolus: synthesizes ribosomes. present in plants and animals. ribosomes: provide sites for protein synthesis. present in all cells. mitochondria: produce energy by aerobic metabolism. present in plants and animals. chloroplasts: perform photosynthesis present in plants. endoplasmic reticulum: synthesizes membrane components, proteins, and lipids. present in plants and animals. Golgi apparatus: modifies, sorts, and packages proteins and lipids. present in plants and animals. Lysosomes: contain digestive enzymes, digest food and worn-out organelles. present in animals. plastids: store food, pigments. present in prokaryotes. central vacuole: contains water and wastes, provides turgor pressure to support the cell. present in plants and animals. vesicles and vacuoles: transport secretory products: contain food obtained through phagocytosis. present in plants and animals. Cytoskeleton: gives shape and support to the cell, positions and moves cell parts. present in all cells. centrioles: produce the basal bodies of cilia and flagella. present in animals.
plasma membranes are hella important:
define compartments and organelles of a cell, regulates passage of materials, participates in biochemical reactions, receives information about the environment, communicates with other cells, act as part of energy transfer and storage.
biological membranes:
plasma membranes physically separate the cell interior from the extracellular environment. Eukaryotes and prokaryotes. membranes also form compartments within eukaryotic cells like organelles.
cell membrane composition:
membranes of the cell are composed mostly of phospholipids. Two layer sheet called a phospholipid bilayer. Hydrophilic head and hydrophobic tail. membranes are not static, rigid sheets. plasma membranes are flexible, self sealing and can fuse with other membranes. the plasma membrane is a fluid mosaic, fluid because molecules can move freely past one another and a mosaic because of the diversity of proteins in the membrane.
extracellular matrix:
connective proteins hold cells together. interstitial fluid facilitates transportation in/out and crosstalk between cells. mainly a eukaryotic cell part. sometimes a prokaryotic cell will develop slime, like when bacteria group together.
nucleus and ribosomes:
genetic control of the cell. the nucleus is the control center of the cell. each gene is a stretch of DNA that stores the information necessary to produce a particular protein. proteins do most of the actual work of the cell. the nucleus is separated from the cytoplasm by a double membrane (lipid bilayer x2) called the nuclear envelope. pores in the envelope allow certain materials to pass between the nucleus and the surrounding cytoplasm. RNA Nucleolus products. Nucleolus inside nucleus, makes pieces of ribosomes.
the relationship between DNA, chromatin and a chromosome
DNA is wound around histones, and this coils tightly like a spring to form chromatin. an entire linear strand of DNA coiled into chromatin is a chromosome. They’re all DNA at different levels of organization and important to distinguish.
