exam #1 Flashcards
define life
the condition which distinguish animals, plant, fungi, protist and bacteria from inorganic objects and dead organisms
characteristics of living systems
- cellular organization2. ordered complexity3. response to stimuli4. growth through metabolism5. homeostasis6. development7. reproduction8. evolution
how is the scientific method used to study living systems?
- make observations2. hypothesis construction3. hypothesis testing4. data analysis5. conclusion6. repeat
elements found in living systems
-C, O, H, N -Na, Cl, P, K, S, Fe, Mg - trace amounts
covalent bonds
-strong bonds (single, double, triple)-occur when elements share electrons-form discrete molecules-occur WITHIN molecules
hydrogen bonds
-weak association/weaker than covalent-easy to break and reform-involve 2 polar molecules-occur BETWEEN molecules
ionic bonds
-opposite charges attract-compounds are electrically neutral -atoms not paired, but associate with all other opposite charges in the vicinity-water disrupts these bonds by separating the ions or dissolving the crystals
non-polar
electrons shared equally
polar
electrons spend more time in part of the molecule
cohesive
attraction between water molecules
adhesive
attraction with other polar molecules
impact of temperature on the properties of water
-high specific heat-high heat of vaporization (vaporizes when all hydrogen bonds are broken)-low density of ice
solution = – + –
solvent + solute
substances that can form hydrogen bonds in water are those substances that can form hydrogen bonds with —
water
can things that aren’t polar still dissolve?
yes, but they have to form hydrogen shells
hydrophobic
water hating
hydrophilic
water loving
definition of a cell
smallest unit of life
cell theory
- organisms are composed of one or more cells2. cells are the smallest living thing3. cells arise from the division of a previously existing cell
characteristcs common to all cells
- genetic material - DNA2. cytoplasm3. plasma membrane
what limits cell size?
transportation… the smaller the cell the easier it is to transport things from place to place
diffusion
solvent moves by concentration gradient (area of high concentration to an area of low concentration)
biomolecules
-lipids-proteins-carbohydrates-nucleic acid
properties of lipids
-non-polar-high proportion of hydrogen-carbon bonds-hydrophobic
structure of a lipid
-head - polar, hydrophilic-tail - non-polar, hydrophobic
saturated fat
animal fat, compact tightly, even structure
unsaturated fat
vegetable fats, structure not even because of double bonds
what is the name of the H2N group in an amino acid
amino (nitrogen) group
what is the name of the C group in an amino acid
central carbon group
what is the name of the COOH group in an amino acid
carboxyl (carbonic acid) group, amino acid group
what is the name of the R group in an amino acid
r-group, varies
what is a peptide bond
a bond between amino acids (amino and carboxyl group)
primary structure of an amino acid
amino acid order
secondary structure of an amino acid
hydrogen bonds form between non r-group parts (local interactions)
tertiary structure of an amino acid
large scale folds, gives shape
quaternary structure of an amino acid
multiple polypeptide chains, aggregate (loose things combining)
what is the role of lipids
-loosely defined (insoluble in water)-energy storage
phospholipid bilayer
-boundary-proteins are embedded-composed of 2 layers of lipids-tails facing each other with heads on both sides
functions of protein
-motion-enzyme catalysts-storage-transport in and out of the cell-support-defense-regulation
fluid-mosaic model
-fluid - components always moving, controlled by hydrophobic/hydrophilic properties-mosaic - made of different types of molecules
nucleus
-protects the DNA-double membrane (phospholipid bilayer)-contains chromosomes
ribosomes
-responsible for protein synthesis -(not really an organelle) -present in both prokaryotic and eukaryotic (different sizes)-2 parts - large and small subunits - together to synthesis proteins-located in the cytoplasm and ER - location determines function
endoplasmic reticulum
-responsible for protein transport-located around the nucleus-2 types - smooth and rough
smooth er
synthesizes lipids and carbs
golgi bodies
-protein processing-UPS of the cell-transport proteins and substances
mitochondria
-cell’s power plant-2 sets of membranes - inner fold (lots of SA)
endosymbotic theory
-some organelles originated from prokaryotic cells that were engulfed by early eukaryotic cells -cyanobacteria -> chloroplasts-bacteria -> mitochondrialevidence:1. circular chromosome, prokaryotic-like ribosomes, double membrane-where the mitochondria, chloroplast and nucleus came from
osmosis
diffusion of a substance across a membrane
passive transport
-with concentration gradient-channel proteins-carrier proteins
channel proteins
-sometimes reversible-size restriction
carrier proteins
-large molecules-specific
active transport
-against concentration gradient-requires energy
what is the energy currency of a cell
ATP
what does ATP stand for
adenosine tri-phosphate
prokaryotes
-small-simple-single circular chromosome
eukaryotes
-large-complex-multiple linear chromosomes
differences between animal cells and plant cells
-plants have cell walls for support-plants have chloroplasts for photosynthesis-plants have vacuoles for storage
chloroplasts
-has 2 membranes - outer and an inner-contains ribosomes and DNA molecules
do prokaryotic cells have DNA?
yes, in cytoplasm
do prokaryotic cells make energy?
yes, photosynthesis
do some prokaryotic cells convert sugar into sunlight?
yes, they fold in on them selves
