Cellular Processes Flashcards
(80 cards)
1
Q
Phospholipid labelling
A
Hydrophilic phosphate group head and hydrophobic fatty acid tails
2
Q
Phospholipid bilayer labelling
A
Phospholipid, cholesterol, integral/transport protein, cholestrol.
3
Q
Equilibrium
A
the state obtained when the concentration of molecules is equal. Diffusion stops when this is reached.
4
Q
Facilitated Diffusion
A
The movement of substances through transport proteins (carrier or channel proteins) from an area of high conc to low conc until Equilibrium is reached. - carries larger or polar particles or ions
5
Q
Osmosis
A
Net movement of water across a semi-permeable membrane. - Water moves from an area of high water potential (Hypotonic) to an area of low water potential (Hypertonic)
6
Q
Hypotonic
A
A solution has a Lower conc of solute particles dissolved and high water potential
7
Q
Active transport
A
the movement of prticles from an area of low conc to an area of high conc moving against the conc gradient through a protein carrier
requires energy and coontinues after equilibium is reached
8
Q
Hypertonic
A
A solutions has a Higher conc of solute particles dissolved and Low water potential
9
Q
Lysis
A
When a cell is placed in a hypotonic solution, gains too much water and bursts.
10
Q
Similarities and differences between Passive and facilitated diffusion
A
Both dont use energy and move from high water potential area to low water potential area. Passive moves through phospholipid bilayer, Facilitated moves through channel proteins. Passive involves small, nonpolar molecules, Facilitated uses Larger, polar molecules.
11
Q
Cytosis
A
the bulk transport of substances i and out of the call across the plasma membrane through a protein carrier
12
Q
Endo v Exo Cytosis
A
Endocytosis: the uptaking of substances into the cell by the infolding of the cell membrane over liquid
Exocytosis: bulk Ejection of substances out of the cell using vesicle. Folds over the substances. Removes hormones and enzymes.
13
Q
Plant cell organelle purposes
4
A
Cell wall (Celulose) for structure
Chloroplast for photosynthesis
Large vacuole for water storage
Ribosomes for protein synthesis
14
Q
Cell
A
The most basic unit of a living organism
15
Q
Chloroplast
A
Carries out photosynthesis
16
Q
Cytoplasm
purpose
A
Gives cell shape, carries items inside nucleus, site of biochemical reactions.
17
Q
Mitochondria
A
The purpose of respiration is to produce energy in the form of ATP. ATP is required for all active processes within an organism.
required for cells
18
Q
Nucleus
A
Cntrols cell activity. Contains DNA, Chromosomes, nucleoleus (genetic material)
19
Q
Isotonic
A
when two solutions have equal concentration of solutes across a semipermeable membrane
20
Q
Plasma (cell) membrane
A
controls what enters and exits the cell made up of a semi permeable phospholiipid bilayer
21
Q
Catalyst
A
Something that speeds up a chemical reaction
22
Q
Factors that affect rate of diffusion
A
Temperature- high temp=faster diffusion
Distance- smaller distance=faster rate
Conc gradient-greater distance=faster rate
Particle size- smaller particles=faster rate
PH - if PH rises above or below optimum- ROR may not occur
23
Q
Enzyme
A
A biological catalyst that speed up the rate f chemical reactions in living organisms by lowering the amount of activation energy needed for a reaction to occur. proteins made up of amino acids bonded together in a globular shape
24
Q
Denaturing
A
An enzyme and its ative site can denature meaning its shape and structure is permanently altered as bonds within the enzyme are broken.
25
Simple diffusion
Movement of particles down the conc grdient from an area of high conc to low conc
| does not require energy and stops when equilibrium is reached
26
Active transport protein
protein pump or protein carrier
27
passive transport protein
channel or carrier protein
28
Temp impact on RoR
If temp goes too high above optimum temp the enzyme will denature and going too far below then enzyme activity will decrease leading to fewer successful collisions
29
pH impact on RoR
Ezymes have an optimum pH which affects the bonds holding the enzyme together, if pH rises above or below optimum the altered environment will disrupt the bonds holding the enzyme together and the active site willl change shape and become denatured. In some cases reaction may not be able to occur at all.
30
Substrate conc affect on RoR
At low conc, chances of substrate collisions with ensymes deccreases. At high substrate conc, there are more substrate particles to collide with enzymes so collision chances increase.
31
Active transport
The movement of particles from an area of low conc to high conc going aginst the conc gradient through a protein pump
32
Importance of smaller cells having: Large SA:V
Cells must have a large SA:V for efficient transport of materials into and out of the cell. This is so material trnsport is moving at a fast enough rate to support cellular functions. As the cell has more surface area relative to its volume diffusion disrance decreases, and every part of that volume can be supplied with oxygen at a faster rate.
33
Why cells divide
* Cells are constantly growing and as cells grows SA:V ratio decreases
* If the cell is too large efficency of moving materials into/out (Waste) of the the cell decreases
* Movement of particles is too slow to centre of the cell due to increase in diffusion distance
* Therefore every cell has a limit of SA to V ratio.
* This is crucial to functioning of life processes and survival.
* Therefore cells must divide to increase ratio
34
Temp affect on enzyme action
- Function at an optimum temp
- Too far below optimum- enzyme activity decreases so fewer collisions with enough energy for successful reactions
- Too far above optimum means chznge in environemnt conditions is too strang causinig hydrogen bnds in enzyme to break and the enzmyme will denature
35
pH impact on enzyme action
- Function at optimum pH
- anywhere outside of optimum means the altered chemical environment disrupts the hydrogen bonds holding the enzyme together and will break causing active site to change shape and enzyme will denature
36
Substrate conc impact on enzyme action
- at low conc chances of colliding with substrates is low.
- As conc is increased there are more substrate particles avaliable to collide with enzymes s collison chances increase
- There is a limit to the amoount of enzyme reactions that occur
- This goes until a point of saturation is reached
37
Point of saturation
when all active sites of all the enzymes in a substance are being used to rate of reaction can no longer increase.
38
Chloroplast function and definition
The chloroplast is the organelle inside the plant cells where photosynthesis occurs.
Chlorophyll absorbs different wavelengths of light
Chloroplasts are mostly concentrated at the upper surface of the leaf
(palisade layer) to maximise the rate of photosynthesis- for this is where light
exposure is highest.
39
Photosynthesis
| and equation
ENZYME CONTROLLED
PROCESS that is a chemical
reaction that occurs in the leaf.
Carbon dioxide+water ->(Light energy) Glucose+Oxygen
40
Aerobic respiration
| with equation
Occurs in the Mitochondria
Oxygen+Glucose -> Carbon dioxide+water+36ATP
41
Anaeriobic respiration
| With Equation
Occurs in Cytoplasm
Glucose -> Lactic acid + 2ATP
42
Advantages and disadvantanges of aerobic
Adv=No Lactic acid, more efficient energy production
Disadv=Slower, requires O2 to occur
43
Advantages and disadvantages of Anaerobic
Adv= Fast, Does not require O2
Disadv=Less efficient energy production, lactic acid buildup
44
Waxy Cuticle function
Thin clear waterproof layer- allows penetration of light that is
needed for photosynthesis to the cell layers below that contain
chloroplasts.
45
Palisade cell layer function
Palisade cells are near the top of the leaf and contain the most
chloroplasts. They are large rectangular cells arranged vertically
packed tightly
46
Spongey mesophyll function
provides second chance for light to be absorbed
The cells are more rounded and arranged further apart with air
spaces between them.
To allow efficient diffusion of the gases (carbon dioxide and
oxygen) through the leaf.
47
Stomata and Guard cell function
Stomata
Pores in the underside of the leaf.
Allow gases in (carbon dioxide) and out (oxygen) of leaf (simple diffusion)
Guard Cells
Open/close stomata
Helps reduce water loss from the leaf as it is required for
photosynthesis
48
Vein cells functions
Deliver water from the roots to the cells in the leaf, and carries
away glucose made by leaf cells to other parts of the plant, and
therefore photosynthesis can continue efficiently as it needs water
as a reactant
Xylem- transports water and minerals from the roots up the plant stem
and into the leaves.
Phloem- transports glucose made in leaves to rest of plant.
49
Photosynthesis and its purpose
| with Equation
to produce glucose that can be used in the process of respiration to produce the energy needed for life processes.
Water+Carbon Dioxide ->(Light energy) Oxygen+Glucose
50
Labelling the Chloroplast
* Inner membrane
* Outer membrane
* Chlorophyll
* thylakoid
* Granum
* Stroma
Other factors: has a semipermeable membrane
chlorophyll is the pigmment that makes the plant green and is located in the thylakoid
Membrane is thin to allow light through
| Note is rod shaped with 2 layers and 3x3 thylakoid discs
51
Labelling the mitochondria
* Outer membrane
* inner membrane(on the inside but protruding fold)
* Cristae (folding of inner membrane, labelled at inner fold)
* Matrix (very middle)
| Note has a rod shape with splat shaped inside
52
Leaf structure main points
* Waxy cuticle
* upper/lower epidermis
* Palisade layer
* Spongey layer
* Guard cells + Stomata
53
Enzyme controlled processes
* Respiration
* DNA replication
*Photosynthesis
54
How does glucose enter/exit cell
facilitated diffusion
55
Chloroplast is the site of
Photosynthesis
56
How does CO2 enter the leaf cells
from area of high conc to low conc through simple diffusion via the stomata
57
How does water enter the leaf
Enters the plant through the root hair cells by Osmosis.
58
Light dependant phase
| PHOTOLYSIS STAGE
Light dependant reactin takes place in the thylakoid within chloroplast. Light energy is absorbed in the pigment chlorophyll. This light energy splits water into H+ and O. H+ goes to the light independant process which O is excreted as a waste product. (Via stomata) or O can be used by the plant for cellular respiration. (aerobic)
H+ will be transported by NADPH to dark phase.
59
Light independant phase
| aka Dark phase/Calvin phase CARBON FIXATION STAGE!!!
Takes place in the stroma (liquid matrix of the chloroplast) ATP produced in previous hpase breaks down to ADP+P. NADPH provides H+ to stroma. release of energy enables CO2 gas to combine with protons H+ thrugh a series of reactions to form a glucose molecule.(Carbon fixation)
60
During the light dependant phase water is split into
Hydrogen and Oxygen where Oxygen is the waste product
61
Glucose and what it is used for
C6H12O6 - After glucose is made during photosynthesis it is either used fr cellular respiration or stored as a starch
62
Substrates eg:
Water or Carbon Dioxide
63
Enzymes are composed of
Hydrogen and thus it is present in stroma of chloroplast to bind to CO2 in dark phase
64
As cell size increases
SA:V ratio gets smaller
| this is bad
65
Why cells are forced to divide
This is because as cell grows and SA:V gets smaller meaning diffusion distane will increase and get too long causing inefficient diffusion. This means cells must divide in order to decrease in size and increase their SA:V ratio to maintain sufficient diffusion
66
Mitosis
| define and purpose
where a body (somatic) cell divides for growth and repair
The purpose is to prduce new, genetically identical cells for growth and repair and to maintain a large SA:V ratio in the cell. The daughter cells function the same way as the parent cell.
ATP is required for mitosis to occur no energy=cell death as no cells divide
67
Label DNA replication
Parent strand
Hydrogen bond
Nitrogenous base
Daughter strand
Sugar-phosphate backbone
Nucletide
68
DNA Replication
Enzyme controlled Process that makes a copy of the double-stranded DNA molecule.
Purpose is to copy the cells DNA before Mitosis do that after cell division each new cell will have a cmplete set of identical genetic iniformation.
Replicated DNA is used in the daughter cells to ensure that ew daughter cells carry ut same functions as parent cells
69
DNA replication -> Mitosis
DNA replicatin must ocur before Mitosis as mitosis requires 2 genetically identical chromosomes. IF DNA replication fails to replicate fast enough it will slow or stp the process of mitosis. GROwth+Repair of organisms will be seriiously affected resulting in eventual death.
70
Enzymes+purpose in DNA replication
Helicase=breaks the hydrogen bonds to form the replication fork formation
Primase=reads the corresponding bases and places a primer whiich indicates the complimentary base
DNA polymorase=Reads the primer and put donw the correct bases.
| If this is not done it can result in mutations, and or death
71
DNA replication process
* Helicase unwinds and unzips the double straned DNA exposing the nucleotides
* Each strand of DNA is used as a template
* An enzyme adds complementart nucleotides to the DNA strands using the base pairing rule (A+T)(C+G)
* When all new nucleotides are added along each parent strand, two identical strands are produced.
* An enzyme joins DNA fragments together
* Semi conservative replication occurs where each new DNA molecule formed has one old (from original parents) and one new strand
72
Photosynthesis Relation to Enzymes
* Enzyme define + structure
* Mention active site
* Define photosynthesis with equation
* Mention reactants of Photosynthesis
* Mention light dependent phase with relation to where it occurs
* Mention enzyme-substrate complex
* Mention light independent phase with relation to where it occurs
* Mention enzyme-substrate omplexes
* (if asked mention how each factor affects rate of photosynthesis through enzymes)
* link to rate of reaction based on given factors
73
DNA replication and Mitosis structuring
* State when occurs (before mitsis)
* Mitosis purpose
* daughter cell and function
* Dna replication process
* base pairing rule
* semi conservative
* Mitosis define + purpose
* Organism link to step one of mitosis (Growth), as organism grows more cells must be made
* Repair - as organism damages cells, must repair the tissue
* stages of organism life - different levels of mitosis when mmore/less growth occurs
* SA:V - organism grows - so does cells- inefficient transport - must divide for efficient - life process stop to kill organism - must divide to survive
74
Diffusion in cycle of growth and division structure
* Diffusion define
* process + purpose diffusion
* Cells maintain large SA:V
* What occurs if small (inefficient)
* link to cellular function
* effective transpotr and survival
* O2 diffuse for respiration
* Cell division high when organism growing moments with eg to organisms/plants
75
When mitosis occurs
growth: In the early stages of life, cells need to be rapidly dividing to enable
growth.
This includes infancy, childhood and puberty in animals and seasonal growth (for example in spring time) in plants; as well as
germinating plants
2. REPAIR- Damage to cells or tissue will increase the rate of mitosis
e.g. skin cut or bone break
mitosis is needed for repair once growth has stopped, when organism stops growing mitosis still occurs in the organism.
3. Cells must retain a small size for efficient transport of materials into and out of the cell.
Cells divide by mitosis to maintain a large SA:V ratio, so they don’t grow too large.
If cells grow too large, diffusion distance from membrane to centre of
cell is too long- 1) life processes stop 2) cell death 3) organism cannot
survive.
76
Important words
Enzyme substrate complex
Cellular functions
Life processes
Cell survival
77
Grana and Thylakoid functions
Grana - Maximised surface area for light asrobtion to increase amount of h2O split - so mre h+ provided so more glucose made in dark phase
Thylakoid - contain chlorophyll which captures light energy to allow dependent reaction to occur.
78
Stroma functions
clear to allow light
contain enzymes to catalyse reactions
Dark phase occurs here
Closely link the light indpendent and dependent reactions
79
Stages of Respiration
| 3
* Glycolisis(stroma)
* Krebs Cycle (Mitochondira)
* Electron Transport chain (Mitochondria)
80
Co factor
Non protein molecule that attaches to the enzyme, changes active site shape to allow the enzyme to bind the the substrate. Is necessary for enzyme action
