Cell Organelles Flashcards
What is the function of the Cell-surface membrane?
Structure: found in all cells, phospholipid bilayer
Functions: controls the entrance and exit of molecules
What is the function of the Nucleus?
Key structures: Nuclear envelope (double membrane), Nuclear pores, Nucleoplasm, chromosomes, Nucleolus (smaller sphere inside, site of rRNA production).
Functions: Site of DNA replication, contains the DNA for each cell, Site of ribosome synthesis.
What is the function of the Mitochondria?
Structure: Double membrane with inner membrane called the cristae, fluid center called the mitochondrial matrix, loop of mitochondria DNA
Function: Site of aerobic respiration, Site of ATP production, DNA to code for enzymes needed in respiration.
What is the function of the Chloroplasts.
Structure: surrounded by double membrane, contains thylakoids (folded membranes embedded with pigment), fluid filled stroma contains enzymes for photosynthesis, found in plants.
Function: site of photosynthesis
What is the function of the Golgi apparatus and Golgi vesicles?
Structure: folded membranes making cisternae, secretory vesicles pinch off from the cisternae.
Function: Adds carbohydrates to proteins to form glycoproteins, Produce secretory enzymes, secrete carbohydrates, transport modify and store lipids, form lysosomes, molecules are labelled with their destination, finished products are transported to cell surface memory in secretory vesicles where they fuse with the membrane, contents are released.
What is the function of the Lysosomes?
Structure: bags/vesicles of digestive enzymes- can contain 50 different enzymes.
Function: Hydrolyze phagocytic (bacteria) cells, completely breakdown dead cells (autolysis), exocytosis- release enzymes to outside of cell to destroy material, digest worn out organelles for reuse of materials
What is the function of the Ribosomes?
Structure: small, made up of two sub-units of proteins and rRNA, 80S are large ribosomes found in eukaryotic cells, 70S Smaller ribosomes found in prokaryotic cells, mitochondria and chloroplasts.#
Function: site of protein synthesis
What is the function of the Rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER)?
Structure: rough and smooth ER both have folded membranes called cisternae, rough have ribosomes on the cisternae.
Function: RER - protein synthesis for proteins destined to leave the cell, transported through RER and into secretory vesicles
SER- synthesis and store lipids and carbohydrates
What is the function of the Cell wall?
Structure: found in plants and fungi, in plants its made of microfibrils of the cellulose polymer, in fungi its made of chitin
Function: provides structural strength
What is the function of the Cell vacuole?
Found in plants. A single membrane sac filled with fluid containing salts, sugars, and amino acids. The membrane around a cell vacuole is called the tonoplast. To provide support to a cell, store amino acids and sugars, and can contain pigments to attract pollinators.
What is the function of the Cytoskeleton?
Structure: A network of fibers found within the cytoplasm all over a cell, Consists of microfilaments, microtubules and intermediate fibers
Function: Provides mechanical strength to cells, helps maintain shape, microfilaments are responsible for cell movement, microtubules are responsible for creating a scaffold structure, intermediate fibers provide mechanical strength.
What is the function of the flagellum
Structure: Whip like structure
Function: Allows for mobility, and sometimes as a sensory organelle for chemical stimuli.
What is the function of the cillia
Structure: Hairlike projections out of the cell
Function: Can be mobile or stationary, Mobile cilia help move substances in a sweeping motion, Stationary cilia are important in sensory organs such as the nose
Do electron or light microscopes have a higher resolution?
Electron
What is the function of centrioles?
Structure: Made of microtubules and occur in pairs to form centrosome.
Function: Involves in the production of spindle fibre and organization of chromosomes in cell division
