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Define a cell
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Differentiate between unicellular and multi-cellular, animal and plant cells
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How do we study cell function
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What do you mean by fracturnation?
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Name the types and parts of the microscope
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The three main parts of the cell
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Organelles and their functions
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The cell cycle, why do cells divide?
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The characteristic the plasma membrane
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The lipid by-layer and fluid mosaic
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What are the parts of the control center of the cell
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What are the functions of the plant cell wall
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Name the 3 main types of intercellular links Animal cell, what are their functions
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What are “The cell theory”
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What are the differences between the Eukaryotes & Prokaryotes
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What is the plasma membrane made up of
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What do you mean by amphipathic
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What are the functions of the cholesterol molecules and protein
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What is selective permeability
 Explain “Diffusion depends on concentration gradients”
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What is dynamic equilibrium?
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Hydrophobic vs Hydrophobic
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What do you mean by passive
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What are Osmosis, facilitated transport, dynamic equilibrium, concentration gradient, active transport
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Membrane junctions, three types
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What are Hypertonic, Hypotonic and Isotonic solutions
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Plasma membrane, Phospholipids, amphipathic
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What strengthens the fluid mosaic and makes it more stable
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What are Diploid and Haploid Number of chromosomes
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Where does the gene reside, Sex and body chromosomes
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Define mitosis and meiosis
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What do yo mean by crossing over

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Mother cells vs daughter cells
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The Human somatic or Body cells and sex cells, the phases of cell division
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What is binary fission?
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Tell what is happening at each phase of cell division PMAT, Interphase
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What is crossing over, when does this occur
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What is Cytokinesis
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Differentiate between mitosis and Meiosis
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Metabolism refers to all to the chemical reactions within a cell
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These include catabolic and anabolic reactions
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Catabolism : this is the chemical reaction that breaks down large substances into smaller ones with the release of energy
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Anabolism : this is the systemic chemical reactions in which the products are larger than the reactants, ex aa to protein
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Energy coupling: this is the use or transfer of energy generated during catabolism (exergonic reaction) to drive anabolism (endergonic reaction)
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Energy
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Energy is the ability to do work
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Energy exists in many forms
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Kinetic energy: this is the energy of motion
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Potential energy: this is the energy of position
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Chemical energy: this the energy stored in molecules
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There are also mechanical, heat and light energy, radient
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Energy can be transformed from one form to another
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Bioenergetics : this is the study of how organisms manage their energy resources
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Thermodynamics : this is the study of the energy transformation that occur in a collection of matter
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First law of energy : energy cannot be created or destroyed, but can be transformed or transferred
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Second law of energy : every energy transfer or transformation increases the entropy
(disorderliness) of the universe
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Third law of energy
: the quantity of energy in the universe is constant, but it’s quality is not
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Spontaneous VS non-spontaneous process
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A spontaneous process can take place with out any outside help, ex. The flow of water down the hill
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A non-spontaneous process cannot occur on it’s own.
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Energy is expended for this to take place, ex. Machine pumping water into a water tank tower
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What is Free energy :
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The proportion of the system energy that can perform work when temperature is uniform throughout
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What is Exergonic reaction : this is a spontaneous chemical reaction in which there is a net release of free energy
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What is Endergonic reaction : this is the type of reaction in which free energy is absorbed from the surrounding ( a non-spontaneous chemical reaction)
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ATP (Adenosine Triphosphate ): this is the energy source for the cells
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It is composed of a nitrogen base adenine, the sugar ribose and three phosphate group

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ATP is used in the body cells for anabolic reactions, active transport, nervous conducting and muscle contraction.
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ADP (Adenosine Diphosphate): it is similar in structure to ATP except for the phosphate group
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ATP has 3p, whereas ADP has 2 phosphate group
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ADP is produced when ATP is hydrolyzed
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Enzymes
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An enzyme is a protein catalyst that speeds up chemical reaction
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They regulate the speed at which a chemical reaction occur without affecting the end product of the reaction and without being used up in the reaction
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Energy of activation : this is the energy that must be provided to cause molecules to react with one another
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Enzymes are substrate specific
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Wht is a substrate? is a reactant in a reaction controlled by an enzyme
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Ex. Reactant enzyme
Substrate Product
Sucrase
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Sucrose + Water Glucose +Fructose
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Factors affecting enzyme activity
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Temperature : - rate of reaction decreases with rise in temperature
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Enzyme is denatured beyond optimal temperature
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Ph : the optimal values ranges from 6 – 8 with a few exception
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For pepsin the optimal ph is 2
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Cofactor : enzyme may be bound tightly to active site as permanent residents
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•
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What are cellular respiration, mitochondria
The overall process is:
Organic compounds + O2 CO2 + H2O + Energy
Glucose.
C6H12O6 + 6O2 6CO2 + 6H2O + Energy (ATP + heat)
686 kcal per mole of glucose
What is Phosphorylation
What is Oxidation-reduction reactions, or redox reactions
The three metabolic stages of respiration are ?
In which part of the cell do Glycolysis and krebs cycle occur
How many ATP produced by one mole of glucose?
How many % of ATP is used for work and heat?
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Photosynthesis is the conversion of light energy to chemical energy which is stored in the form of glucose or other organic compounds
Photosynthesis occur in plants, algae and certain prokaryotes
6CO2 + 12H2O + light energy C6H12O6 + 6O2 + 6H2O
Where does photosynthesis occur

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Light vs dark cycle
An autotroph is an organism that obtains organic food molecules without eating other organisms
An autotroph is a primary producer or biosphere producer
Autotrophs use energy from the sun or from oxidation of inorganic substances to make organic molecules
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Heterotroph s
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They are organisms that obtain food molecules by eating other organisms or their by products
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They are the biosphere consumers
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Decomposers
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These are saprotrophic fungus and bacteria that absorb nutrients from non-living organic materials and convert them into inorganic forms (fungi and bacteria)
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Plants usually store their food in the form of starch
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Photoautotrophs (light – self – feeding)
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Almost all autotrophs depend on photosynthesis and the byproduct of photosynthesis for food and oxygen
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Chloroplast : the green coloring matter in plants green leaves, stem and fruits
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Chloroplast is an organelle found in plants and photosynthetic protists that absorb sunlight and uses it to drive the synthesis of organic compounds from CO2 and H2O
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Chlorophyll: this is the pigment in the chloroplast of plants
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Chlorophyll is directly involved in light reaction
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It converts solar energy into chemical energy
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Light reaction is a Redox reaction – the reverse of ATP production
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C6H12O6 + 6O2 = 6CO2 + H2O + Energy
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Two stages of photosynthesis
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Light reaction converts solar energy to chemical energy
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Electron and hydrogen are transferred from water to NADP
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Oxygen is released in this process
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ATP and NADP are produced in the light reaction
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A phosphate group is added to ADP (phosphorylation )
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No sugar is produced
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Carbon fixation
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This is the incorporation of carbon into organic compound
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This is the beginning of the Calvin cycle
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The fixed carbon is reduced by addition of electrons (energy from NDP)
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Carbon dioxide is converted to carbohydrate using the ATP generated from the light cycle
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Therefore, calvin cycle produces CHO in plants
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No light is required (dark reaction
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Light cycle: in the thylakoides of the chloroplast
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Calvin cycle: in the stoma
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Cells must communicate in order to coordinate their activities in a way that enables the organisms to develop from a fertilizes egg and then survive and reproduce in turn
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What is a target cell?
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Cell signaling: a method of regulation in all living things
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Signaling originating from another cell or from some changed in the organisms physical environment can be received by cells in various forms
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Receptors

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Cells respond to electromagnetic signals – light
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Cells respond to mechanical signals – touch
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Cells most often communicate with each other using chemical signals
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A signal from cell is converted into specific cellular response in a step called signal transduction pathway
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Cells communicate by releasing chemical messengers targeted for cells that may not be immediately adjacent
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Intracellular communication
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Neural communication
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Neurotransmitter: transmits impulse along the nervous system (chemical signal) ex ACH
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The impulse diffuse into the nerve cell and passed from one nerve fiber to another across the narrow synaptic cleft (gap)
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What is a neurotransmitter, give example
Endocrine communication
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Hormone or endocrine signaling
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A specialized cell releases the hormone into the blood system which transport it to the target cells; ex. Insulin and the reproductive hormones (gonadotropic - LH, FSH (ICSH)
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Paracrine communication :
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The product of the cells diffuse into the extracellular fluid (ECF) to affect neighboring cells that may be some distance away
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Autocrine communication :
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Cells secret chemical messengers that bind to receptors on the same cell
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In paracrine signaling, numerous cells can simultaneously receive a response to the molecules of growth factor produced by a single cell on their vicinity (growth factor)
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Animal cells may communicate via direct contact between molecules on their surfaces
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This is important in embryo development and operation of the immune system
Three stages of cell signaling
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Receptor :
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The target cell that detects the signal from outside the cell
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A chemical signal is detected when it binds to a cellular protein
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Molecule binding initiates the process of Transduction
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Transduction : converts received signal to a form that can bring about a specific response
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This may occur in a single step
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Often requires a sequence of changes in a series of different molecules
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Response: transduced signal triggers a specific cellular response
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Ligand : a molecule that binds specifically to a receptor site of another molecule
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***Ethylene*** this is a plant hormone (C2H4) that promote fruit ripening, a hydrocarbon with only six atoms