Life Processes

Front 1

Diffusion

Back 1

Movement of substance along conc. grad. which exists until equilibrium is reached. Passive Movement. Begins fast and then slows.

Front 2

Factors Effecting Diffusion

Back 2

Molecule size, temperature (amount of kinetic energy), concentration gradient difference, diffusion distance, any physical barriers

Front 3

Osmosis

Back 3

Movement of water from a low (concentrated solution) to a high (dilute) concentration through a semi permeable membrane. Passive movement

Front 4

If a cell has lost of water...

Back 4

Hypotonic (animal, may burst) or turgid (plant)

Front 5

If a cell has a normal amount of water...

Back 5

Isotonic (animal), flaccid (plant)

Front 6

If a cell has hardly any water...

Back 6

Hypertonic (animal), Plasmolysed (plant)

Front 7

Active Transport

Back 7

Movement from a high to low concentration against the concentration gradient or movement along concentration gradient above that which does not require energy input; energy is required.

Front 8

Phagocytosis

Back 8

Engulfs solid materials and buds off to form a vesicle. Requires energy

Front 9

Ions Pumps

Back 9

Actively accumulate specific ions into the cell, often exchanging them for another (requires energy)

Front 10

Enzyme

Back 10

Catalyse biochemical reactions without being altered or used up, acting on substrate to break or join molecules together

Front 11

Activation site of a substrate

Back 11

Made of polypeptide chain folded in such a complex manner that often only one kind of substrate can react. Lowers the activation energy required and provides an easier/shorter reaction pathway. Promotes reaction.

Front 12

Cleft of an enzyme

Back 12

Draws in substrate and promotes reaction, fits with substrate like a 'lock and key' and then carries out induced fit to put pressure on the substrates bonds.

Front 13

Effect of temperature and pH levels on enzyme

Back 13

If too low, low rate (not enough kinetic energy for substrate molecules and enzymes to combine and then less likely to have Eact). If too high then the enzyme can denature (exact shape alters) and reaction stops.

Front 14

Enzymes are effected by...

Back 14

pH levels, temp., co-factors, concentration (although is too much plateaus) and inhibitors (may compete with substrate or bond to enzyme altering the exact shape.)

Front 15

Catabolic reactions (enzymes)

Back 15

Single molecule drawn into cleft and chemical bonds are broken. Two new products formed (digestion, respiration). When the molecule bonds to the enzyme with weak chemical bonds, its own bonds are weakened so reaction can progress readily

Front 16

Anabolic reactions (enzymes)

Back 16

2 Substrate molecules drawn into cleft. Chemical bond formed, fuse substrate together.

Front 17

Enzyme Co-factors

Back 17

Slightly alter or complete the active site to make the enzyme more reactive

Front 18

Photosynthesis Equation

Back 18

6Carbon Dioxide + 12Water --> (with sunlight and chlorophyll) --> 6Water + 6Oxygen Gas + Glucose (C6H12O6)

Front 19

Thylakoids

Back 19

Light-dependent phase. The thylakoid membrane contains protein complexes which catalyse the light reactions

Front 20

Chlorophyll

Back 20

Absorb light energy at specific frequencies, not green, (found in thylakoids) and the electrons in the chlorophyll gain this energy (photons) from the sun and become very unstable (have too much energy).

Front 21

Cutcle and Upper Epidermis

Back 21

Protective, transparent layer (allowing sunlight through), waxy and waterproof cuticle.

Front 22

Palisade Caells

Back 22

Contain chloroplasts where majority of photosynthesis occurs. Close to the top of the leaf for maximum light.

Front 23

Spongy Mesophyll

Back 23

Loosely packed so gases can circulate and easily reach the palisade cells (CO2 in and )2 out)

Front 24

Stomata

Back 24

Allow gases and water vapour in/out of the leaf. Controlled by guard cells.

Front 25

Phloem and Xylem

Back 25

Phloem transports sugars around the plant and xylem water (mainly from the roots).

Front 26

Cytoplasmic Streaming

Back 26

Carried out in the palisade cells and is where the chloroplasts move around the outside of the cell. At one end they are refreshed with CO2 from the air spaces in the spongy mesophyll and at the other (top) they are gaining light energy.

Front 27

Grana

Back 27

Stacks of Thylakoids (joined together by lamella)

Front 28

Stroma

Back 28

Where Calvin Cycle occurs at it contains RDP and the enzymes require to break down CO2 in C3 and catalyse reaction to produce glucose.

Front 29

Light Dependent Phase

Back 29

The unstable, high energy electrons are passed thorough energy acceptors who capture the excess energy and give it to energy carrying molecules ADP and NADP (become ATP and NADPH). The H+ ions are also produced during the photolysis of water which occurs when the H2) molecule gains light energy and splits into H+ and OH-. H+ goes to NADP become a high energy molecule and the OH= is converted to H2O and 1/2O2 which is released as waste.

Front 30

Calvin Cycle

Back 30

The CO2 combines with RDP to produce a very unstable 6C molecule which then breaks into 2x C3 molecules which combine with Hydrogen and using the energy from NADPH and ATP from glucose.

Front 31

Respiration Equation (aerobic)

Back 31

Process in which an organism breaks down food and sugars to proude useable energy.
Glucose + 6 O2 ----> 6 Water + 6 CO2 + 38ATP

Front 32

Respiration Equation (anaerobic) Without Oxygen supply (glycolysis stops unless a alternative H+ acceptor is formed.

Back 32

Glucose ---> Pyruvate -----> Alcohol and CO2 (in plants) OR Lactic acid (in animals)

Front 33

Role of ATP

Back 33

Universal energy carrier which quickly releases energy through the hydrolysis of the terminal phosphate. Once the phosphate bond is broken and energy is released becomes ADP and must carry out respiration

Front 34

Glycolysis

Back 34

Glucose broken down into pyruvate (from C6 to C3 molecule) uses to ATP and produces 4ATP with a net gain of 2ATP. Releases CO2 as it completes this process

Front 35

Transition Reaction

Back 35

Must be in the presence of O2. Pyruvate breaks down into the C2 molecule, again producing CO2, acetyl. This C2 molecule is very reactive so combines with Co-enzyme A, forming acetyl coA

Front 36

Kreb's Cycle

Back 36

The acetyl coA goes through a cycle releasing electrons, H+ ions and CO2 as it joins with oxytal acid and forms citric acid. The H+ ions and high energy electrons combine with the NAD and FAD (becoming NADH2 and FADH) which are high energy molecules. Net gain of 2 ATP.

Front 37

Electron Transport System

Back 37

High energy protons (H+ ions) and electrons are unstable and cannot combine with the oxygen as their energy is too high so go through a chain of energy accepting enzymes which capture the energy lost as the particles pass through the chain and convert this energy into ATP. The oxygen acts as the final proton acceptor and forms water. All energy released is captured forming 34 ATP.

Front 38

Matix

Back 38

Kreb's Cycle. Plentiful ribosomes producing enzymes to help the reaction occur at a faster rate.

Front 39

Cristae

Back 39

Electron Transport System as there are energy acceptor enzymes set up in a long chain which can accept the energy from the H+ and the electrons to produce the ATP. High surface area, can absorb a lot of O2.

Front 40

Cystoplasm

Back 40

Glycolysis as it already contains the glucose and enzymes required for this reaction to occur.

Front 41

Chromasomes

Back 41

Made from coiled of DNA and make body proteins known as genes. Come in homologous pairs (one chromosome from each parent) and carry genetic information for the same features.

Front 42

Why does mitosis occur?

Back 42

As a cell grows the SA:V ratio increases so diffusing becomes insufficient and the cell must divide through mitosis (limit to the amount of substance a cell can absorb per second). Growth, replacement asexual reproduction, development e.t.c.

Front 43

Cell Cycle

Back 43

First Growth (normal metabolic activities) --> Synthesis (DNA Replication) --> 2nd Growth (prepare for mitosis) --> Mitotic (Mitosis)

Front 44

Interphase

Back 44

Chromosomes are copied, shorten, fatten and become visible pairs (not dividing)

Front 45

Prophase

Back 45

Membrane around nucleus breaks down

Front 46

Metaphase

Back 46

Chromosomes line up in the middle of the cell

Front 47

Anaphase

Back 47

One chromosome from each homologous pair goes to each end of the cell, pulled apart by the spindle contracting

Front 48

Telophase

Back 48

Parent cell starts splitting into two identical daughter cells

Front 49

DNA Replication

Back 49

DNA helicase unzips strand and DNA polymerise adds new nucleotide (pairing A to T and C to G) forming a complementary strand so chromosome forms double strand apperance

Front 50

Semi Conservative

Back 50

Half of the new DNA strand is the original DNA