sem 2 final: part 1 Flashcards
characteristics of life (7)
excretion, growth, homeostasis, metabolism, nutrition, reproduction, response
how do eukaryotes versus prokaryotes divide?
eukaryotes divide through binary fission, mitosis, or meiosis whereas prokaryotes divide only through binary fission
binary fission
asexual reproduction, offspring arise from a single parent cell and the offspring is genetically identical to the parent cell
process of binary fission
- parent cell prepares for reproduction 2. prokaryotes replicate DNA before cell division 3. 2 DNA molecules each attach to a different part of the cell membrane and build more membrane to elongate the cell 4. the cells successfully divide and are genetically identical to parent cell
the fleming discovery
mold drifted through the air and stopped the spread of a bacteria that had been growing, afterwards fleming found that the mold contained a self-defense chemical which led to the discovery of penicillin
florey and chain
testing of penicillin involving mice from where they proved it to be effective
homeostasis
keeping conditions inside of the cell within tolerable limits
Difference between eukaryotes and prokaryotes
Eukaryotes are animals/plants, prokaryotes are bacteria/archaea. Eukaryotes are bigger, prokaryotes are smaller. Eukaryotes have DNA in their nucleus, prokaryotes have DNA in their nucleoid. Eukaryotes have larger 80s ribosomes, prokaryotes have smaller 70s ribosomes.
Cation versus anion
Cation is positively charged whereas anion is negatively charged
Covalent bond
Chemical bonds formed by the sharing of electrons between atoms
Hydrogen bonds
Weak interactions that are responsible for cohesion and adhesion
Adhesion
Water molecules hydrogen bonding to another kind of molecule (capillary action)
Cohesion
Water molecules sticking to each other through hydrogen bonding (surface tension)
Catabolism
Breakdown of complex molecules from simpler molecules
Anabolism
Synthesis of complex molecules from simpler molecules
Polymer
consists of large macromolecules repeatedly bonded together
4 major classes of carbon compounds
lipids, carbohydrates, nucleic acids, and proteins
Saturated versus unsaturated fatty acid
Saturated fatty acids have no double bonds and unsaturated fatty acids have double or triple bonds
Cis- versus trans- fatty acid
Cis- fatty acid causes a straight chain and a trans- fatty acid causes a bend in the chain.
Channel membrane proteins
have a pore/channel that allows transport of substances in and out of the cell
Carrier membrane proteins
bind to substances on one side of the membrane and then change shape to transport them to the other side
Recognition membrane proteins
help cell in differentiating between self and non-self cells
Receptor membrane proteins
span the whole cell membrane to relay info. in and out of the cell
Endosymbiotic theory
explains origin of eukaryotic cells (originally prokaryotes that were taken in by larger prokaryotic cells and remained inside host cells instead of being digested/broken down), cells that could provide energy became mitochondria, cells that could convert light energy to chemical energy became chloroplasts
Passive transport
is diffusion and osmosis, it does not require energy
Active transport
is bulk transport via pump proteins, does require energy
Simple diffusion
process of transport that does not require help from membrane proteins
Facilitated diffusion
process of transport that does require help from membrane proteins
Osmosis
passive movement of water molecules from low to high concentration
Effect on a cell in a hypertonic, hypotonic, ad isotonic environment
Hypertonic: cell will shrink (higher concentration of solutes). Hypotonic: cell will enlarge (lower concentration of solutes). Isotonic: cell will remain the same size.
Endocytosis versus exocytosis
ENDOCYTOSIS: cells take in molecules by engulfing them through pinocytosis (cell drinking) and phagocytosis (cell eating). EXOCYTOSIS: molecules are ejected from the cell via excretion.
