Cell Biology Flashcards
Exceptions to the cell theory
Striated muscle, Giant Algae, Fungal Aseptate Fungi.
As a cell grows larger, its SA: VOL becomes _______
smaller.
Descirbe the davson-danielli model
the bilayer of phospholipids in the centre of the membrane with layers of protein on either side.
How did the Singer-Nicolson Model falsify the Davson-Danielli model?
Freeze fracture showed parts of the surface were hydrophobic and the globular protein was present in the center of the phospholipid bilayer.
Identify the structure of the Fluid Mosiac Model (Membrane structure)
Phospholipid bilayer, Integral proteins, Peripheral Proteins, Glycoproteins, Pumps or Channel proteins, Cholesterol,
What does amphipathic mean?
Part of the molecule is attracted to water and the other part is not attracted to water.
What does cholesterol regulate in the cell?
Cholesterol molecules are hydrophobic, meaning it restricts the movement of the phospholipid bilayers. It reduces the fluidity and permeability of the membrane.
Diffusion
passive movement of particles from a region of high concentration to a region of lower concentration as a result of the random movement of particles through a partially permeable membrane.
Facilitated Diffusion
Using channel proteins, they allow certain substances to pass through.
Define abiogenesis
Process of making life when there was no life before
who and how did they falsify spontaneous generation
Louis pastur, by controlling factors like broths, boiling the broths and the shape of the tube.
Who and how did they falsify abiogenesis
Miller and urey, by recreating the atmospheric conditions of 4.5 billion years ago, With excess ammonia, methane and carbon dioxide. By creating the conditions back then, inorganic molecules became organic molecules.
How can we prove endosymbiosis?
Second membrane in mitochondria and chloroplast. They also have separate dna which suggests that eukaryotes englufed smaller prokaryotes to form a symbiotic relationship.
