Cells Flashcards
Differences between eukaryotes and prokaryotes
Eukaryotes have membrane bound organelles
Prokaryotes are much smaller
Prokaryotes have free moving unbound organelles
Describe the structure of a mitochondria
They have an outer membrane and a very curved inner membrane to create a greater surface area. They have their own DNA and 70s ribosomes.
Describe the structure of a chloroplast
They have a double membrane, and contain their own DNA and 70s ribosomes. They contain starch grains for energy, and chlorophyll is found in thylakoids. The thylakoids are stacked into granums.
What is endosymbiosis and what evidence for it is there
The theory that eukaryotes organelles originated from prokaryotes. It is believed a large prokaryotes engulfed a smaller prokaryotes and that became an organelle. The evidence for this is that mitochondria and chloroplasts have different DNA from the rest of the cell and so suggests they originated somewhere outside the cell
What is a mitochondrion
Produces ATP from aerobic respiration
What is the smooth ER
Involved in the synthesis and transport of lipids
What is the rough ER
Involved in the synthesis and transport of proteins
What is a ribosome
Site of protein synthesis
What is the Golgi body
Completes the production of enzymes and proteins and produces secretory vesicles for exocytosis
What is a lysosome
Contains powerful enzymes that can fight pathogens or recycle organelles
What is a centriole
During cell division, centriole organise the microtubules that support the cell
What is a chloroplast
Contains chlorophyll which traps light energy for photosynthesis
What is a vacuole
Used for storage and for upholding the structure of the cell
What is the nucleus
Contains DNA which controls all cell processes
What is chromatin
Condenses to form chromosomes in cell division
What is the nuclear envelope
A double membrane surrounding the nucleus
What is the nucleolus
The site of ribosome production
What is a plasmodesmata
The site in a plant cell wall where there is no cellulose so a strand of cytoplasm from one cell can link with another
What are flagella
Responsible for the movement of prokaryotes
What is a bacteria cell wall made of
murein (polysaccharide)
What is a plasmid
Circular DNA which replicate independently
What is the capsule
A gummy layer around bacteria which helps it colonise
How do prokaryotes photosynthesise without chloroplasts
they have a photosynthetic membrane
What are microvilli
They increase the surface area of a cell for better absorption and secretion
What is the cytoskeleton made of
Filaments, microtubules and actin
What are protoctistas
Usually single-celled organisms that are simple eukaryotes because they have simple organelles
What word can be used to describe virus’
Acellular
What are virus’s known as outside a cell
virions
Properties of virus’
No organelles
either DNA or RNA not both
Not perceived to be alive
