Eukaryotic cell structure Flashcards
Name the parts of a eukaryotic cell
Nucleus, mitochondria, chloroplasts, ER, golgi apparatus, lysosomes, ribosomes, cell wall, vacuole, cell membrane, cytoplasm
Name the parts of the nucleus and describe its main function
Contains genetic material which controls what the cell does. Nuclear envelope Nuclear pores Nucleoplasm Chromosomes Nucleolus
Describe the function of the nuclear envelope
is a double membrane surrounding the nucleus connected to the ER and controls the entry and exit of materials
Describe the function of nuclear pores
allows the transport of large molecules e.g messenger RNA out of the nucleus
Describe the function of the nucleoplasm
granular, jelly-like material that fills the nucleus (contains chromosomes)
Describe the function of chromosomes
Carries genetic information in the form of genes and made up of nucleic acids and proteins
Describe the function of the nucleolus
contains nucleoplasm and makes RNA and ribosomes (can have more than 1 in a nucleus)
Name the parts of mitochondria and describe its main function
Site of aerobic respiration and produces ATP.
Double membrane
Cristae
Matrix
Describe the the function of the mitochondria’s double membrane
- Controls the entry and exit of material
- Outer membrane: covers like a skin
- Inner membrane: folds into layered structures (increases surface area)
Describe the function of the cristae
- Folds inside made by the inner membrane
- Larger surface area (more space) for chemical reactions to take place e.g attachment of enzymes/proteins for respiration
Describe the function of the matrix
- Fluid contained within it
- Ribosomes, DNA, proteins and lipids floating in it
- Contains granules which help with ion concentrations
- Produce proteins
- Many enzymes involved in respiration found here
Name the parts of chloroplasts and describe its main function
The site of photosynthesis.
Chloroplast envelope
Grana
Stroma
Describe the function of the chloroplast envelope
- Similar to the structure of the mitochondrial double membrane
- Very selective in what can leave and enter the chloroplast
Describe the function of the grana
- Stacks of discs known as thylakoids (resembles a stack of coins)
- Site of light-dependent reactions of photosynthesis (1st stage of photosynthesis)
- Connected by intergranal thylakoids
- Within thylakoids is chlorophyll
Describe the function of the stroma
- Colourless fluid surrounding grana which contains enzymes required for photosynthesis
- DNA and ribosomes are present so proteins can be quickly and easily made for photosynthesis
- Where 2nd stage of photosynthesis (synthesis of sugars) takes place
- Contains starch grains
Name the two types of ER and describe the difference in their function
Rough ER -
Contains ribosomes for protein synthesis
Large surface area for protein and glycoprotein synthesis
Pathway for transport of materials e.g proteins
Smooth ER - To store, synthesise and transport lipids and carbohydrates
Describe the function of the golgi apparatus
- Produce secretory enzymes, form glycoproteins (made from carbohydrates and proteins) and lysosomes
- Secrete proteins and carbohydrates e.g used in making plant cell walls (for carbohydrates)
- Transports, modifies and stores lipids
Describe the function of the cytoplasm
Where chemical reactions e.g anaerobic respiration take place
Describe the function of the cell membrane
Controls what goes in and out of the cell
Describe the function of lysosomes
- Releases strong enzymes which break down and destroy material around the cell (exocytosis)
- Hydrolyses material ingested by phagocytic cells
- Digest worn out cell organelles so that useful chemicals they are made up of can be reused
- Completely break down cells after they have died (autolysis)
Describe the function of ribosomes and the main differences between the two types
- The site of protein synthesis.
- Made up of two subunits (1 large and 1 small) containing ribosomal RNA and proteins.
- 80S ribosomes - found in eukaryotic cells
- 70S ribosomes - found in prokaryotic cells, mitochondria and chloroplasts (slightly smaller)
Describe the function of the cell wall
- Gives the cell strength and structure to prevent cell bursting by osmosis
- It is also made of cellulose and other polysaccharides
- Allows water to flow through it
- There is a thin layer called middle lamella which marks boundaries between adjacent cell walls and cements cells adjacent together
Describe the function of the vacuole
- Gives the cell structure and stores cell sap (mainly water but also mineral salts, sugars + amino acids)
- Support herbaceous plants + herbaceous parts of woody plants by making cells turgid
- The sugars + amino acids can be temporary food stores
- Pigments may colour petals to attract pollinating insects
- Single membrane around it is the tonoplast
