Advanced Revision Flashcards
Flagellum Definition
6 marks
Microscopic hair-like organelle used by cells + microorganisms for movement.
- In Latin ‘Flagellum’ means whip, just like the whipping motion flagella (plural) often use for locomotion.
Specialised flagella
4 marks
Are used in some organisms as sensory organelles that can detect changes in temp + pH.
Flagella are filamentous protein structures found in
3 marks
Archaea, eukaryotes + Bacteria (most commonly).
Typical Flagella Use
6 marks
- To propel a cell through liquid - e.g bacteria + sperm
- To increase reproduction rates (in some eukaryotic cells )
Unique Flagella Uses
4 marks
Recent studies show flagellum may also be used as a secretory organelle, but this discovery needs more time to be fully understood.
The Movement of Eukaryotic Flagella
2 marks
Depends on adenosine triphosphate (ATP) for energy.
The Movement of Prokaryotic Flagella
3 marks
Gets its energy from the proton-motive force/ion gradient, across the cell membrane.
Active transport requires
1 mark
An input of energy to occur.
Concentration gradient is a
3 marks
A region of space over which the concentration of a substance changes.
Active Transport vs Facilitated Diffusion;
Differences
(7 marks)
Active transport works against the concentration gradient, moving substances from areas of low concentration to areas of high concentration. Facilitated diffusion often goes down the concentration gradient but can move freely in + out of the Cell
The types of proteins that they use are different.
ATP is the primary…?
2 marks
Energy carrier in living things.
Regeneration of ATP is important because
5 marks
Cells tend to use up (hydrolyze) ATP molecules very quickly + rely on replacement ATP being constantly produced
Active transport vs Facilitated Diffusion;
Similarities
(2 marks)
Both use proteins to assist in transport.
The Process of Active Transport is ‘Active’ because
3 marks
It requires the use of energy (usually in the form of ATP) - It is the opposite of passive transport.
ATP Hydrolysis Reaction
9 marks
ATP + H20 ⇋ ADP + Pi (small i) + energy
Pi (small i) stands for
7 marks
An inorganic phosphate group;
(PO^3-) - small 3- on top, small 4 on bottom
4
ATP Structure
5 marks
At the center of the molecule lies a five-carbon sugar, ribose, which is attached to the nitrogenous base adenine + to the chain of three phosphates.
What are the 3 phosphate groups on the Structure of an ATP; in order of closest to furthest from the ribose sugar, labeled?
(3 marks)
Alpha, Beta, + Gamma.
Carrier Proteins - Motive Force
9 marks
The movement of the ion/molecule is passive, but proton motive force for the carrier protein is provided by said proton or pH gradient and/or electrical gradient - set up by the proton pumps
What is ATP made unstable by?
4 marks
3 adjacent negative charges in its phosphate tail, which are repellent of each other.
Proton Motive Force
9 marks
When electron carriers embedded in the cell membrane react to a Chemical/molecule - energising the membrane. This energy can be stored in the ATP for later or put to work (like the energy obtained in Prokaryotic Flagellum)
What are the bonds between the phosphate groups, in the structure of an ATP, called?
(3 marks)
High-energy Phosphoanhydride bonds.
ATP vs ADP;
Rechargeable Battery Analogy
(7 marks)
ATP - charged battery, has energy that can be used to power cellular reactions.
Once the energy has been used up;
- Uncharged battery (ADP) must be recharged before it can again be used as a power source.
The ATP Regeneration Reaction
9 marks
Energy + ADP + Pi (small i) ⇋ ATP + H20
The reaction of ADP + Pi (small i) to ATP requires ______.
1 mark
Energy
Enthalpy
3 marks
Thermodynamic quantity equivalent to the total heat content of System.
Enthalpy is equal to
3 marks
the internal energy of the System + the product of pressure + volume.
Entropy
3 marks
Thermodynamic quantity representing the unavailability of a systems thermal energy for conversion into mechanical work.
Entropy is also interpreted as
5 marks
The measure of the number of possible arrangements the atoms in a System can have
- causes a degree of disorder or randomness in a System
Thermodynamic Meaning
7 marks
The relations between heat + other forms of energy (such as mechanical, electrical, or chemical energy)
- by extension, of the relationships between all forms of energy.
ATP Recycling
4 marks
Quantity of ATP in human body = 0.2 moles
- typically remains constant as it is recycled from ADP.
Free energy released during ATP Hydrolysis
- Under standard conditions
(9 marks)
ΔG for the Hydrolysis of 1 mole of ATP into ADP + Pi (small i) is
7.3kcal/mol (or 30.5kJ/mol) standard conditions - during removal of 1 phosphate group.
1 Phosphate Group is removed during
5 marks
Hydrolysis
- by breaking a phosphoanhydride bond, energy is released + ATP is converted to adenosine diphosphate (ADP).
Standard conditions for ATP Hydrolysis
5 marks
1M concentration of all Molecules 25°C + pH of 7.0
Free energy released during ATP Hydrolysis
- Under non-standard conditions
(7 marks)
ΔG for the Hydrolysis of 1 mole of ATP in a living Cell is almost double the value at standard conditions
- around 14kcal/mol (-57kJ/mol)
ΔG
6 marks
- Amount of free energy available to do work
- Equal to the sum of the enthalpy + the product of temp and entropy
Gibbs Free Energy
6 marks
Thermodynamic potential
- that can be used to calculate the max reversible work that may be performed by a Thermodynamic System at a constant temp + pressure
ADP Molecule Structure
9 marks
Sugar backbone attached to Adenine;
which is attached to 1’ Carbon
+ 2 Phosphate Groups of ATP bonded to the 5’ Carbon of the sugar backbone
Name for Sugar backbone + Phosphate connection
3 marks
Sugar-Phosphate Backbone
Gibbs Free Energy Calculation
5 marks
ΔG = ΔH - T ΔS
Gibbs Free Energy is Measured In
1 mark
Joules
ΔG can predict
3 marks
Direction of the chemical reaction under 2 conditions
- Constant temp
- Constant pressure
If ΔG is positive
3 marks
Reaction is non spontaneous
I.e an input of external energy is necessary for the reaction to occur
If ΔG is Negative
3 marks
Then it is spontaneous
Occurs without external energy input
What are Smooth Muscles?
12 marks
Type of muscle tissue which is used by various systems to apply pressure to vessels and organs.
They contract (graded contractions) under certain stimuli as ATP is freed for use by the myosin, found in the cell - the amount released depending on the intensity of the stimuli.
What is Smooth muscle composed of?
7 marks
Sheets or strands of smooth muscle cells - which have Fibres of Actin and Myosin supported by a framework of other Proteins.
Where are Smooth Muscles found?
4 marks
In the walls of hollow organs like your intestines and stomach (they work automatically without you being aware of them).
Examples of Smooth Muscles and their Jobs
9 marks
Muscular walls of your intestines contract to push food through your body.
Muscles in your bladder wall contract to expel urine.
Smooth muscles in a woman’s uterus (or womb) help to push babies out of the body during childbirth.
Graded Contractions
11 marks
To exert a greater force, a series of nerve impulses would be sent at higher frequency to the muscle - using more Axon brush nerve endings responsible for a Motor Unit.
Muscle with motor units containing more/less muscle fibres would be responsible for giving rough/delicate responses.
Involved in the transmission of impulses
2 marks
Axon brush nerve endings
What are each Axon Brush Nerve Endings responsible for?
2 marks
A fixed number of muscle fibres.
What is a Motor Unit?
3 marks
The group of Muscle Fibres responding to a specific nerve ending.
Muscle with Motor Units containing less Muscle Fibres is responsible for?
(1 mark)
Giving delicated responses.
Muscle with Motor Units containing more Muscle Fibres is responsible for?
(1 mark)
Giving rough responses.
For a faster response (contraction) there would be what contracting at any time?
(1 mark)
Muscle fibres
Muscle Tone
2 marks
Muscle fibres contracting at any time.
If the proportion of Muscle Fibres contracting in a piece of muscle is higher
(2 marks)
The Muscle Tone is higher.
If the proportion of Muscle Fibres contracting in a piece of muscle is lower
(2 marks)
The Muscle Tone is lower.
Determines the Muscle Tone
2 marks
Proportion of Muscle Fibres contracting in a Muscle.
3 benefits for keeping the Muscle Tone
6 marks
- It is important in the maintenance of body postures.
- It keeps muscles contracting and reduces the chance of degeneration of muscles.
- The maintenance of Muscle Tone enables the body to give response faster.
ADP molecule - Structure
9 marks
- 5’ Carbon; Sugar (Ribose) backbone attached to Adenine
- Adenine is attached to 1’ Carbon
- 2 Phosphate Groups of ATP; bonded to 5’ Carbon Sugar backbone
ATP to ADP: Reaction Type
1 mark
Hydrolysis
ADP to ATP: Reaction Type
1 mark
Condensation
ATP to ADP: Enzyme Involved
1 mark
ATP Hydrolase
ADP to ATP: Enzyme Involved
1 mark
ADP Synthase
Energy Profile of Reaction: ATP to ADP
1 mark
Release Energy
Energy Profile of Reaction: ADP to ATP
1 mark
Requires Energy
The hydrolysis of ATP can be coupled to energy-requiring reaction and used to
(2 marks)
Phosphorylate compounds.
The condensation of ADP to form ATP can occur during
2 marks
Respiration and photosynthesis.
Phosphorylate
5 marks
To cause (an organic compound) to take up or combine with phosphoric acid or a phosphorus-containing group.
What makes up the Cytoskeleton?
7 marks
Microfilaments (also known as Actin Filaments), Intermediate Filaments, Microtubules, Flagellum, Motile Cilia + Centrosomes.
What are Histones?
4 marks
A type of protein, DNA molecules wind around to form Chromosomes in the Nucleus.
What is the job of the Golgi Apparatus?
4 marks
Modifies molecules (e.g. lipids, proteins) produced by the Cell; such as folding for proteins
- packs them into Vesicles and ships them (and other materials) around/outside of the cell.
What is the Nucleolus?
2 marks
Small area within the Nucleus where Ribosomes are made.
What are Lysosomes?
5 marks
Specialised vesicles in which protein enzymes are contained.
- They break down macromolecules (waste, food + worn out cell parts) into their components for further use by the cell.
What are Vacuoles?
7 marks
Small storage pockets formed of a single membrane layer
- containing gas (such as O2 or CO2) or fluid (such as water) found within cells.
- Found in Animal Cells.
What are Ribosomes?
4 marks
Organelles made of RNA + Protein
- are either attached to the Endoplasmic Reticulum or suspended in the Cytosol.
- they facilitate Protein Synthesis.
