Cell Structure Flashcards
What is a eukaryotic cell?
Cell that contains DNA in a nucleus and is MEMBRANE-BOUND.
It is MULTICELLULAR.
Animal.
Plant.
Algae.
Fungi.
What is a prokaryotic cell?
Cell where DNA is free in the cytoplasm and is NOT membrane-bound.
It is UNICELLULAR.
Bacteria.
What are some examples of eukaryotes?
Animal cells
Plant cells
Algae
Fungi
What are some examples of prokaryotes?
Bacteria.
What are the differences between eukaryotes and prokaryotes?
Eukaryotes =
membrane-bound organelles
multicellular
DNA enclosed in nucleus
Prokaryotes =
not membrane-bound organelles
unicellular
DNA is free in cytoplasm.
Smaller
What is a multicellular organism?
Multicellular organisms use many different cells to function.
What is a unicellular organism?
Made up of only 1 cell that carries out all of the functions needed by the organism,
What is the cell membrane made out of?
Phospholipid bilayer.
Glycolipids
Glycoproteins
Cholesterol
Mainly lipids & protein.
What is the difference between a membrane and a cell-surface membrane?
A cell-surface membrane is the membrane surrounding the cell’s surface.
A normal membrane is the membrane around organelles?
What are cells made up of?
Organelles.
Remember… Year 9?
Cells, cells, they’re made of organelles!
What are the features of a nucleus?
NUCLEOPLASM =
contains chromosomes
Site of DNA synthesis
NUCLEOULUS =
(central region)
assembles ribosomes.
NUCLEAR ENVELOPE =
double membrane w/ nuclear pores to let substances exit/enter cell.
State the relationship between specialised cells and a system.
Specialised cells form…
Tissues that perform specific function that form…
Organs made of dif tissue types that form…
Organ systems
What is the function of cell-surface membranes?
Controls what molecules enters and leave the cell.
What is the structure and function of mitochondria?
= Structure =
Has DOUBLE MEMBRANE.
Inner membrane is folds to form CRISTAE (the inner layer of membrane inside)
Contains SHORT, CIRCULAR DNA.
Fluid MATRIX (gap inside mitochondria) contains enzymes involved in respiration.
= Function =
SITE of AEROBIC RESPIRATION to produce ATP (releases energy)
What is the structure and function of ribosomes?
= Structure =
Ribosomes have NO MEMBRANE.
Float freely in cytoplasm or attached to RER.
= Function =
Produces polypeptides from amino acids to form proteins.
What is the structure and function of a cell wall?
= Structure =
Made of CELLULOSE in plants & algae.
Made of CHITIN in fungi.
Made of MUREIN in prokaryotes.
= Function =
Supports cell providing rigidity and prevents them losing their shape.
Physical barrier against pathogens.
What organisms contain cell walls?
Plants
Bacteria
Algae
Fungi
What is the cell wall in plants made of?
Cellulose
What is the cell wall in fungi made of?
Chitin
What is the structure and function of the vacuole?
= Structure =
Single membrane called TONOPLAST.
Some pigments are found in the vacuole.
= Function =
Temporary food store containing sugars & amino acids.
Absorbs & hydrolyses harmful substances to detoxify cytoplasm.
When vacuole is full of fluid the cell becomes turgid (may burst)
Describe the structure and function of chloroplasts.
= Structure =
Contains DOUBLE MEMBRANE.
Small, flattened structure.
THYLAKOID membranes form stacks called GRANA (which contains chlorophyll)
Grana are connected by LAMELLAE (thin, flat pieces of thylakoid membrane)
= Function =
ABSORBS light for photosynthesis to produce carbohydrates.
Photosynthesis can happen in grana or stroma (body)
What key words are associated with chloroplast?
Thylakoid membrane
Double membrane
Grana / granum (singular)
Lamellae
Stroma