hard topics Flashcards
v =
u + at
v squared =
u squared + 2as
s =
ut + 1/2at^2
vt - 1/2at^2
s =
1/2 (u + v)t
I =
Q/t
V =
E/Q
V =
IR
P =
IV = I^2R = V^2/R
E =
ItV
Rt =
product / sum
two resistors in parallel
Rt =
R1/n (for n identical resistors in parallel)
R1/R2 =
V1/V2 (series circuits)
specific heat capacity =
thermal energy/mass x temperature change
density =
mass / volume
P =
F/A
hydrostatic P =
height x density x g
PV =
constnat
c =
fλ
angle of incidence =
angle of refleciton
n1/n2
V1/V2
Vp/Ip
VsIs
F =
BI l
a =
v-u /t
W =
mg
F =
ma
E =
Fd
GPE =
mgh
KE =
1/2 mv^2
E =
1/2 Fx = 1/2 kx^2
p =
mv
P =
E/t
effiency =
useful energy out/total energy in
alpha decay loses
4 from mass number
2 from atomic number
beta decay loses
atomic number gains 1
(a proton turns into a nuetron and a positron and electron neutrino are emitted in the process. then ucleus loses a proton in this process so atomic number decreases by 1)
how does blood travel around the heart
right atrium
right ventricle
pulmonary artery
lungs
pulmonary veins
left atrium
left ventricle
arteries
carry oxygen rich blood away from the heart
capillaries connect
veins and arteris
veins
carry oxygen poor blood from body tissue back to the heart
the aortic valve connects
left ventricle and aorta
mitral valve connects
left atrium and left ventricle
pulmonary valve connects
left ventricle and pulmonary artery
tricuspid valve connects
right atrum and right ventricle
oxygen enters your body from
the inferior vena cava and superior vena cava
describe voltage in series circuits
shared between the components
describe current in series circuits
same across the citcuit
describe total resistance in series circuits
is the sum of the indiviual resistance
describe voltage in parallel circuits
voltage is the same across all components
describe current in parallel circuits
shared between branches
describe total resistance in parallel circuits
always less than the branch with the lowest resistnace
describe genetic engineering
i. taking a copy of a gene from (DNA/chromosomes of) one organism.
ii. insertion of that gene into the DNA of another organism.
iii. the roles of restriction enzymes and ligases.
what happens during electrolysis
an electric current is passed through an ionic substance that is either molten or in solution. The movement of the ions is able to complete the circuit and thus allow the flow of electricity. However, in the process, the ions gain or lose electrons at the cathode and the anode respectively. This change in their oxidation state causes them to become atoms or molecules.
what type of current MUST be used in electrolysis
direct current
why cant an alternating current be used in electrolysis
would result in the electrodes flickering very quickly between being positive and negative. This would mean that the ions wouldn’t be attracted to one particular electrode, therefore would not be able to form the desired atoms or molecules.
the short side of the dry cell in the circuit is
negative (connected to the negative electrode)
the long side of the dry cell is
positive (connected to the positive electrode)
the negative electrode (cathode) attracts
cations
positively-charged cations gain electrons and are thus reduced (reduction takes place here).
the positive electrode (anode) attracts
anions
(negative charges attracted to the positive terminal). It is known as the anode. The negatively-charged anions lose electrons here and are oxidised.
what is produced in electrolysis of molten solutions
elements of the analyte
what is produced in electrolysis of aqueous solutions
an aqueous salt solution and a mixture of gases as the final product
what happens at the cathode in molten electrlysis
cations gain electrons (reduction)
what happens at the anode in aqueous electrolysis
anions lose electrons (oxidation)
in electrolysis, the metal will be produec if
it is less reactive than hydrogen.
Hydrogen will be produced if the metal is more reactive than it.
what is electroplating
a clever way of using the prinicples of electrolysis to coat the surface of one metal with another metal.
FSH
tells the ovaries to prepare an egg for ovulation.
oestrogen
repairs and thickens the uterus lining
LH
causes the egg to be released
progesterone
mantains the lining of the uterus
hormonal contraception
Oral contraceptive pills
Injections
Implants
Skin patches
Hormonal intrauterine devices (IUDs)
non hormonal contraception
Barrier methods such as condoms or diaphragms
Non-hormonal IUDs
Spermicidal agents
Surgical sterilisation
Abstaining from sexual intercourse
amylase
Breaks down starch (carbohydrate) into simple sugars. Produced by the salivary glands, pancreas and small intestine
protease
Breaks down proteins into amino acids. Produced by the stomach, the pancreas and the small intestine
lipase
Breaks down fats (lipids) into glycerol and fatty acids. Produced by the pancreas and the small intestine
food pathway
mouth –> oesophagus –> stomach –> small intestine –> large intestine –> rectum –> anus
gall bladder
stores bileand releases it when needed
pancreas
Produces a whole host of enzymes (amylase, protease and lipase) that help digestion. Its secretions also help neutralise stomach acid
small intestine
Absorption of digested nutrients. Also produces amylase, protease and lipase.
large intestine
Absorption of water from undigested food
rectum
storage of faeces
liver
Produces bile, which neutralises stomach acid (so it doesn’t burn a hole in your small intestine) and helps break up fat globules into smaller globules (emulsification)
stomach
Stores food to slow down its progression along the digestive system. Breaks food up by muscular contractions. Partial digestion of proteins by the enzyme pepsin (a protease). Produces hydrochloric acid to kill bacteria and allow pepsin to work.
aquous copper sulfate electrolysis half equation at the cathode
Cu2+ + 2e– ⟶ Cu Reduction
aquous copper sulfate electrolysis half equation at the anode
2H2O – 4e– ⟶ O2 + 4H+ Oxidation
or
2H2O ⟶ O2 + 4H+ + 4e–
functional enzymes are
present at all times in the circulation and perform a
physiologic function in the blood , examples of these functional enzymes
include lipoprotein lipase , pseudocholinestrase and enzymes of blood
coagulation .
These enzymes are synthesized and secreted by the liver .
non functional enzymes are
plasma also contains numerous other enzymes
that perform unknown physiologic function in blood . These non
functional plasma enzymes arise from the routine normal destruction of
erythrocytes , leukocytes , and other cells . Tissue damage or necrosis
resulting from injury or disease is generally accompanied by increasing in
the levels of several non functional plasma enzymes . Therefore several
enzymes are used in the diagnosis .
out of visible light, which has the highest and lowest wavelength
purple has the shortest
red has the longest
do EM waves perform ultrasound
no
is infrared ionizing
no
which qualities are the same for resistors in series
resistance
voltage
current
power
if two benzenes were fused, what would the ratio of carbons to hydrogens be
the hydrogens should always be lower because one is lost at everyjunction
eg c12H10
what does repeating results do
increase reliability NOT accuracy
what does insulin do
lower blood glucose concentration
when blood glucose is low,
less amounts of insulin is produced and more glucagon is
what produces insulin
the islets of langerhans in the pancreas in the beta cells
A therapeutic gene added to a gamete cell will be found
in every cell in the body of a person developing from that gamete
unit of voltage
watt per amp (power/current)
what type of transmores are used ot decrease the voltage from transmission cables
step down
what do step down transformers do
decrease voltage for safer distribution
do high currents or low curretns waste more energy
high.
do high voltages or low voltages waste more energy
low
why are higher coltages used in transmission cables
to decrease energy loss from them in the form of heat, as this lowers the current.
how many cells does mitorsis produce
2
how many cells does meiosis produce
4
filament bulbs have increased resistance as
temperature rises
are LDR’s ohmic
no as the current and PD are not necessarily proportional
when do the resistanzce of LDRs increase
in dark conditions
where does haemolysis take place
spleen
in series, the total resistance is
equal to the sum of each resistor
The voltage across resistors in a series circuit is
proportional to the resistance of each resistor,
Why do the overhead transition cables in the National Grid have very high voltages?
Lower current and lower resistance mean in turn less energy is lost to the surroundings.
