Cells (eukaryotes And Prokaryotes) Flashcards
Functions of nucleus
Control centre of cell through production of mRNA and tRNA- protein synthesis
Retain genetic material of cell as DNA and chromosomes
Manufacture ribosomal RNA and ribosomes
Nuclear envelope
Double membrane surrounding nucleus
Outer membrane continuous with endoplasmic reticulum, ribosome on surface
Controls entry and exit of materials
Contains reactions
Nuclear pores
Allow passage of large molecules like mRNA out of nucleus
Nucleoplasm
Granular jelly like material
Bulk of nucleus
Chromosomes
Consist of protein bound linear DNA
Nucleolus
Small spherical region within nucleoplasm
Manufactures rRNA
Assembles ribosomes
Can be more than one in a nucleus
Mitochondrion
Rod shaped
Site of aerobic stage of respiration, production of ATP
Mitochondria double membrane and cristae
Double membrane surrounds mitochondria and controls entry and exit of material
Inner membrane folds to form cristae- extensions
Cristae provide a large surface area for the attachment of enzymes and other protein involved in respiration
Mitochondria matrix
Reminder
Contains proteins lipids ribosomes and DNA so mitochondria can control production of own proteins
Many enzymes involved in respiration found here
Chloroplasts
Carry out photosynthesis
Disc shaped
Harvest sunlight
Chloroplast envelope
Double plasma membrane around it
Highly selective in what it allows to enter and leave the chloroplast
Grana, thylakoids, chlorophyll
Grana- stacks of thylakoids, light absorption occurs
Thylakoids- disc like, contains photosynthetic pigment chlorophyll, can join with others in adjacent grana via tubular extensions
Stroma
Fluid filled matrix
Synthesis of sugars (next stage of photosynthesis)
Contains starch grains
Photosynthetic adaptations: granal membranes
Provide large surface area for attachment of chlorophyll, electron carriers and enzymes that carry out light absorption
Photosynthetic adaptations: stroma fluid
Possess all enzymes needed to make sugars in second stage of photosynthesis
Photosynthetic adaptations: chloroplasts
Contain both DNA and ribosomes so they can quickly and easily manufacture some proteins for photosynthesis
Endoplasmic reticulum
3D system of sheet like membranes spreading through cytoplasm
Continuous with outer nuclear membrane
Membranes enclose a network of tubules and flattened sacs called cisternae
Rough endoplasmic reticulum
Ribosomes on outer surfaces of the membrane
Provide a large surface area for the synthesis of proteins and glycoproteins
Provide a pathway for the transport of materials- like proteins throughout the cell
Smooth endoplasmic reticulum
Lacks ribosomes
More tubular
Synthesises stores and transports lipids
Synthesises stores and transports carbohydrates
Golgi apparatus
More compact SER
Consists of cisternae and vesicles (small rounded hollow structures)
Proteins and lipids produced by ER are passed through Golgi apparatus in sequence
Modifies proteins, adds non protein components to them
Labels proteins for sorting and to be sent to right destination
Modified proteins an lipid transported in Golgi vesicles which can move to the cell surface and fuse with the membrane and release contents to outside
Functions of Golgi apparatus
Add carbohydrates to proteins to form glycoproteins
Produces secretory enzymes
Secrete carbohydrates eg for making cell walls
Transport modify and store lipids
Form lysosomes
Lysosomes
Formed when vesicles produced by Golgi apparatus contain (digestive)enzymes like proteases and lipases
Contain lysozymes that hydrolyse cell walls of certain bacteria
Releases enzymes to outside or into a phagocytic vesicle within the cell
Hydrolyses old cell organelles for eg
Name 2 features of HIV particles that are not found in bacteria
Capsid
RNA transcriptase
Nucleoid
Protein envelope
Describe how the scientist will use the information from the colorimeter and her calibration curve to determine the pO2 in a sample of lugworm blood
Measure absorption/ transmission
Plot into calibration curve
Membrane bound organelles
Lysosomes
Mitochondria
Chloroplasts
Golgi body
Endoplasmic reticulum
Golgi vesicles
Function of capsule
Extra protection against immune system
Murein
Glycoproteins
Bacterial cell wall main component
Ribosomes
Made from protein and rna
Vacuole
Contains sugars and salts (cell sap)
Turgid
Specialised cells
A cell with an adaptation specific to its function
Tissue
A group of cells working together to perform a specific function
Eg epithelial tissue
Organ
A group of tissues working together to perform a specific function
Eg small intestine
Organ system
A group of organs working together to perform a specific function
Eg digestive system
Describe viral replication
Attachment proteins attach to receptors
Viral nucleic acid enters cell
Nucleic acid replicated in cell OR reverse transcriptase makes DNA from RNA
viral proteins made by cell
Virus assembled and released from cell
