Beginnings of Life Flashcards
(22 cards)
Amino acids polymerise into…
Proteins
Life requires not just a collection of macromolecules, but…
Compartmentalisation
Purines and pyrimidines polymerise into…
Polynucleotides
Features of the plasma membrane
Selectively permeable, important for communication with outside environment, aids in binding and adhering
Cell theory states that
Cells are the fundamental units of life, all organisms are composed of cells, all cells come from preexisting cells
The cel was first described by…
Robert Hooke in 1665
The cell was first observed through a microscope by…
Anton van leeuwenhoek in 1674
Cell size=
Surface area/volume
Electron microscopes can detect…
Small molecules to plant/animal cells
Light microscopes can detect…
Chloroplasts to fish eggs
Bacteria
Prokaryotic, no nucleus, lack distinct organelles
Archea
Prokaryotic, no nucleus, lack distinct organelles
Eukarya
Eukaryotic, membrane-enclosed nucleus, other compartments and organelles
Gram -ve bacterial cell wall
Has a layer of lipopolysaccharde and protein enclosing a layer of peptidoglycan, some bacteria also have a layer of slime
Mycoplasma
Bacteria that lack a cell wall, making them resistant to antibiotics and pathogenic to humans
Cyanobacteria
Have a complex and organised system of internal membranes which carry out photosynthesis
Flagella
Corkscrew-like structures found in some prokaryotes
Pili
Thread-like structures which help bacteria to adhere to one another during exchange of genetic material, and to animal cells for protection or food
Some prokaryotes have a helical structure inside the membrane which…
Is responsible for maintaining the structure of the cell
Prokaryotes do not undergo mitosis, instead…
They divide by binary fission
Inclusions
Deposits found within the cytoplasm of prokaryotes which include reserves of lipids, starch, or glycogen
Endospores
Highly resistant to environmental stresses such as extreme temperature or drought
