Biology Flashcards
Cell Doctrine
Schleiden & Schwann. All living things are made up of cells and the products formed by cells. Cells are units of structure and function. All cells arise from preexisting cells.
Prokaryotic Cells
Cells only found in bacteria and cyanobacteria (blue-green algae). These cells lack a true nucelus and organelles.
They have: cell membrane, cell wall, single chromosone with DNA only, ribosomes.
Eukaryotic Cells
Found in all organisms except bacteria. Differentiated by membranes into subcellular structures called organelles, include a nucelus.
What do animal cells not have that plant cells do?
cell wall and chloroplasts
What do animal cells have?
■ a cell membrane ■ a nucleus ■ chromosomes (multiple, with DNA and protein) ■ ribosomes ■ mitochondria ■ Golgi apparatus ■ lysosomes (often) ■ vacuoles (sometimes—they may be small or there may be none) ■ cilia or flagella (often) ■ centrioles
What do plant cells have that animal cells do?
centrioles / flagella/cilia
What do plant cells have?
■ a cell membrane ■ a nucleus ■ a cell wall ■ chromosomes (multiple, with DNA and protein) ■ ribosomes ■ mitochondria ■ chloroplasts (in photosynthetic cells) ■ Golgi apparatus ■ plastids ■ lysosomes ■ vacuoles (one large single vacuole in a mature cell)
Matter
ANything that takes up space (volume)
Energy
The capacity to do work; abstract concept that can be described only as it affects matter. Two types: potential and kinetic
Thermodynamics and its laws
the physics of what is and what isn’t possible due to energy.
First law of thermodynamics: Energy can be
transferred and transformed, but it cannot
be created or destroyed (conservation
of energy).
Second law of thermodynamics: Every
energy transfer or transformation results
in the release of heat from the system to
the rest of the universe.
Cell metabolism
energy management by a cell.
The complex structure of a cell includes
pathways along which metabolism proceeds,
aided by enzymes.
Bioenergetics
the study of how organisms
manage energy, including heat production
and transfer; and regulation of body temperature
(endothermy and ectothermy).
Metabolism
the totality of chemical reactions
that take place in an organism
Anabolism
the metabolic synthesis of proteins,
fats, etc., from simpler molecules;
requires energy in the form of adenosine
triphosphate (ATP).
Catabolism
the metabolic breakdown of molecules
for example, respiration
Cellular respiration
a catabolic pathway for
the production of ATP, in which sometimes
oxygen is consumed as a reactant along with
an organic fuel (food). At other times, the
process proceeds without atmospheric oxygen,
but this is less efficient.
Anaerobic pathway of cellular respiration
Food (especially carbohydrates) is
partially oxidized and chemical energy is
released; however, atmospheric oxygen is
not involved in the process.
Aerobic pathway of cellular respiration
Food is completely oxidized to carbon
dioxide and water, and chemical energy is
released; atmospheric oxygen is involved
in the process. The Krebs cycle, electrontransport
chain, and oxidative phosphorylation
are important concepts here.
Photosynthesis
conversion of light energy into chemical energy, on which, directly or indirectly, all living things depend. Photosynthesis occurs in plants, algae, and certain prokaryotes.
Enzymology
the study of the speed of the
process of transformation of energy in a cell;
enzymes change the rate of a reaction without
themselves being consumed by that reaction.
Diffusion
a movement of cells across the cell membrane. he process by which molecules spread from areas of high concentration, to areas of low concentration. When the molecules are even throughout a space - it is called EQUILIBRIUM
Osmosis
the diffusion of water (across a membrane)
Water will move in the direction where there is a high concentration of solute (and hence a lower concentration of water.
Isotonic Solutions
If the concentration of solute (salt) is equal on both sides, the water will move back in forth but it won’t have any result on the overall amount of water on either side.
Hypotonic Solutions
The word “HYPO” means less, in this case there are less solute (salt) molecules outside the cell, since salt sucks, water will move into the cell.
The cell will gain water and grow larger. In plant cells, the central vacuoles will fill and the plant becomes stiff and rigid, the cell wall keeps the plant from bursting
In animal cells, the cell may be in danger of bursting, organelles called CONTRACTILE VACUOLES will pump water out of the cell to prevent this.
Hypertonic Solutions
The word “HYPER” means more, in this case there are more solute (salt) molecules outside the cell, which causes the water to be sucked in that direction.
In plant cells, the central vacuole loses water and the cells shrink, causing wilting.
In animal cells, the cells also shrink.
In both cases, the cell may die.
cell cycle
the entire life cycle of a
cell including reproduction that occurs in an
orderly sequence.
m phase
division of nucleus and cytoplasm
