Eukaryotic cell structure Flashcards
What are all the organelles of the animal cell?
Cell surface membrane
Mitochondria
Nucleus
Ribosomes
Cytoplasm
Smooth ER
Rough ER
Lysosomes
Golgi apparatus
Vesicles
What makes up the mitochondria?
Matrix - makes up space inside cristae
Cristae - makes up ends of folded membrane
What is the function of the matrix?
Contains enzymes for respiration
What makes up the nucleus?
Nucleolus
DNA
Nucleus pores
Nucleus envelop
What is the function of the nucleolus?
Produces ribosomes
What is the function of the nucleus?
Contains genetic material of cell ( DNA, chromosomes )
What is the function of the mitochondria?
Site of aerobic respiration
What is the function of the cristae?
Extensions on the inner membrane - provide a large surface area to increase respiration
What are all the plant cell organelles?
Chloroplasts
Cell wall
Vacuole
What makes up the chloroplast?
Thylakoid
Stroma (empty space)
Granum ( stack of thylakoids )
What makes up the cell wall?
Microfibrils of cellulose
What makes up the vacuole?
Toniplast surrounding cell sap
What is the cell sap made up of?
Salt
Sugar
Amino acids
What is the structure of the cell surface membrane?
- Thin flexable barrier
- Bilayer which is made up of 2 phospholipid molecules
- Found in both anaimal and plant cells
What is the function of the cell surface membrane?
- Hold the cell together
- Controlls what substances enters and exits the cell
How does the structure of the cell surface mebrane relate to its function?
- Phospholipids allow for lipid soluble substances to enter and leave the cell
- Proteins allow for active transport
- Protein channels are water filled tubes to allow for diffusion across membrane
- Carrier proteins have binding site which change shape to transport molecules
What is the structure of the nucleus?
- Nuclear envelope
- Nuclear pores
- Nucleoplasm
- Chromosomes
- Nucleolus
- Chromatin
What is the function of the nucleus?
- Acts as a controll centre of the cell through the production of mRNA and tRNA > protein synthesis
- Retain the genetic material of the cell in the form of DNA and chromosomes
- Manufacture ribosomal RNA and ribsomes
What is the structure of the nuclear envelope?
- Double membrane that surrounds the nucleus
- Outer membrane is continuous with the endoplasmic reticlum
- Often has ribosomes on surface
What is the function of the nucleur envelope?
- Controls the entry and exit of materials in and out of the nucleus
- Contains the reactions taking place within it
What is the structure of the nucleur pores?
large enough to allow for larger molecules to pass through
What is the function of the nucleur pores?
- Allow the passage of large molecules out of the nucleus e.g. mRNA
What is the structure of the nucleoplasm?
- Contsins enzymes and RNA
What is the structure of chromosomes?
- Protein bound DNA
- Linear DNA
- Thread like structure
What is the function of chromosomes?
-to ensure genetic information is passed to daughter cells
How does the structure of chromosomes relate to its function?
- DNA tightly wrapped and condensed around Histones
- Allowing DNA molecules to fit into cells
What is the structure of the nucleolus?
- Small spherical region within nucleoplasm
What is the function of the nucleolus?
- Manfactures ribosomal DNA
- Assembles ribosomes
What is the structure of the mitochondria?
- Around the organelle is a double membrane
- Inner membrane folded to form extensions known as cristae
- Contains matrix which makes up remainder of mitochondria
What is the function of the mitochondria?
- Site of aerobic respiration
- Production of ATP
How does the structure of mitochondria relate to its function?
- 2 membranes outer and inner where there is space respiration to take place
- cristae folded membranes increasing surface area
What is the function of the cristae?
- Provide a large SA for the attachment of enzymes and other enzymes involved in respiration
What is the structure of the matrix?
- Contains proteins, lipids, ribosomes, and DNA
- Enzymes found in respiration found in matrix
What is the function of the matrix?
- Allows the mitochondria to to control production of own proteins
What is the structure of the chloroplast?
- Disc shaped
- Chlorplast envelope
- Grana
- Thylakoids
- Chlorophyll
- Stroma
What is the function of chloroplasts?
Photosynthesis
How does the structure of chloroplasts relate to its function?
- Granal membranes provide large SA for the attachment of chlorophyll > electron carries and enzyme that carry out first stage of photosynthesis
- The fluid of the Stroma presses all the enzymes needed to make sugars in the second condition stage of photosynthesis
- Chloroplasts contain both DNA and ribosomes > quickly manufacture some of the proteins needed fro photosynthesis
What is the general structure of endoplasmic reticulum?
- Three dimensional system of sheet like membranes spreading through cytoplasm of cells
- Continuous with outer membrane
- Membranes enclose a network of tubules and flattened sacs
What is the structure of RER?
Has ribosomes present on outer surfaces of the membranes
What are the functions of RER?
- Provide a large SA > synthesis of proteins and glycoproteins
- Provide a pathway for the transport of materials (proteins) throughout cell
What is the structure of SER?
General ER structure without ribosomes
What are the functions of the SER?
- Synthesise store and transport lipids
- Synthesise store and transport carbohydrates
What is the structure of the Golgi apparatus?
- Consists of flatten membranes which make up flattened sacs (cistern)
- Small rounded hollow structures > vesicles
What is the function of the Golgi apparatus?
- Add carbohydrates to form glycoproteins
- Produce secretory enzymes
- Secrete carbohydrates > such as those used in making cell walls
- Transport, modify and store lipids
- Form lysosomes
What is the role of the golgi appratus?
Proteins and lipids produced by ER are transported through GA in a strict sequence
What is the function of the vesicles?
- Transport modified proteins and lipids to the cell surface
- Fuse with cell membrane to release contents outside the cell
What is the structure of lysosomes?
- Formed when the vesicles produced by the GA contain enzymes such as proteases and lipases
- Contain lysozymes
What are the functions of lysosomes?
- Hydrolyse material digested by phagocytic cells
- Release enzymes to the outside of the cell (exocytosis) > destroy material outride the cell
- Digest worn out organelles > useful chemicals they are made out of can be re-used
- Completely breakdown cells after they have died (autolysis)
What is the structure of ribosomes?
- Cytoplasmic granule found in all cells
- May occur in cytoplasm or be associated with RER
What is the function of ribosomes?
Protein synthesis
What is the structure of cell walls?
- Consists of microfibrils of the polysaccharide cellulose > embedded in a matrix
- Consistent of a number of polysaccharides
- Thin layer > middle lamella > marks the boundary between adjacent cell walls and cements adjacent cells together
What are the functions of cellulose?
- Provide mechanical strength > prevent cell from bursting under the pressure created by osmotic entry of water
- To give mechanical strength to the plant as a whole
- To allow water to pass across it > to contribute to the movement of water throughout plant
What is the structure of the cell wall of algae?
- Cellulose or glycoproteins
What is the structure of the cell wall of fungi?
- Do not contain cellulose
- Compiled of chitlin and glycoproteins
What is the structure of the vacuoles?
- Fluid filled sac bounded by a single membrane
- Membrane > tonoplast
- Contains a solution of mineral salts, sugars, amino acids, wastes
What are the functions of the vacuole?
- Support herbaceous plants by making cells turgid
- The sugars and amino acids may act as a temporary food store
- Pigments may colour petals > attract pollinating insects
