80 ĐỀ THI THỬ TUYỂN SINH TIẾNG ANH VÀO 10 SỞ GD – ĐT THÀNH PHỐ HỒ CHÍ MINH NĂ...
Photosynthesis and cellular respiration
1.
2. describe the process of
photosynthesis.
1
At the end
of the
lesson, you
should be
able to:
OBJECTIVES:
Determine the materials involved in
photosynthesis and Cellular
Respiration.
2
12. PHOTOSYNTHESIS
Stomata- Pores in a plant’s cuticle through which water and
gases are exchanged between the plant and the atmosphere.
13. PHOTOSYNTHESIS
Chloroplasts - are found mainly in the cells of leaves that capture light
energy in photosynthetic organisms. They are disk-shaped organelles that
contain two main compartments essential to photosynthesis.
Chloroplasts- Organelle where photosynthesis takes place.
15. Photosynthesis
1.Grana- the stacks in thylakoids where light-dependent reactions
take place.
2.Stroma - the second compartment in thylakoids, a fluid-filled
space which are situated outside the grana.
16. Photosynthesis
Thylakoids - they are the first compartments in the chloroplasts.
They are flattened, saclike membranes that are arranged in stacks.
22. Light Dependent Reactions
Step 1: The Light Dependent Reaction begins with light absorption in which
light coming from the sun enters through the chloroplasts.
- Chlorophyll in the Photosystem II absorbs light energy which will excites the
electrons.
25. Light Dependent Reactions
Step 3: Chlorophyll in Photosystem I absorbs sunlight which will
electrons excite.
- Photosystem I have a longer Electron Transport Chain.
26. Light Dependent Reactions
Step 4: Electrons help to bond NADP+ and H+ to become
NADPH.
-ATP create with the bonding of ADP+P..
Step 5: Hydrogen diffuse in stroma
28. Light Independent Reactions
The light-independent reaction (also known as dark reaction or
Calvin cycle).
- It consists of cyclical series of reaction that use to assemble sugar
molecules from CO2 and the products of light reactions.
31. Light Independent Reactions
STEP 1: CARBON FIXATION
• CO2 is attached to a five-carbon sugar (ribulose biphosphate, RuBP). T
process is catalyzed by rubisco, an enzyme.
• It forms a new six-carbon molecule which splits in half to form two
molecules with three carbons each called 3-phosphoglycerate.
32. Light Independent Reactions
STEP 2: Reduction of Glycerate-3-Phosphate.
- ATP is used to convert some of the 3-carbon molecules into a sugar
precursor molecule (glyceraldehyde-3-phosphate, G3P).
•
33. Light Independent Reactions
Step 3: Regeneation of RUBP
-The remaining 3-carbon molecule is converted again to the five-
carbon sugar RuBP using ATP so the cycle can continue.
•
37. ATP
Adenosine triphosphate, or ATP- is the primary carrier of energy in cells.
Adenosine triphosphate (ATP), energy-carrying molecule found in
the cells of all living things. ATP captures chemical energy obtained
from the breakdown of food molecules and releases it to fuel other cellular processes.
41. Cellular Respiration
•
There are three stages of cellular respiration: glycolysis, citric acid
cycle, and oxidative phosphorylation.
42. Glycolysis
•
Glycolysis literally means “splitting of glucose.”
Glucose, a 6-carbon sugar molecule is broken down into two molecules of
pyruvate, a 3-carbon molecule, to produce ATP.
It takes place in the cytosol (a part of the cytoplasm) of the cell.
During glycolysis, oxygen is not required.
It has two phases: the energy investment phase and the energy harvest
phase.
44. Pyruvate Oxidation
Before the citric acid cycle can begin, the two pyruvate molecules
from glycolysis are first converted to acetyl-CoA, a 2-carbon
compound in the outer membrane of the mitochondria.
45. CITRIC ACID CYLE OR KREBS CYLE
- It takes place in the mitochondrial matrix of eukaryotes.
-When pyruvate is converted to acetyl-CoA, it is the only time that
the citric acid cycle takes place in the mitochondrial matrix.
46. CITRIC ACID CYLE OR KREBS CYLE
1. The Krebs Cycle itself actually begins when the Acetyl-CoA
combines with the 4C molecules oxoaletic acid (OAA) to produce the
6 carbon molecules citric acid. This reaction catalyzed by the enzyme
citrate synthase.
47. CITRIC ACID CYLE OR KREBS CYLE
2.With the aid of the enzyme acotinase the citric acid now goes
through a series of reaction that release energy. Water molecule is
removed from the citric acid and its put back but in a different
location. OH group is moved from the 3 to 4 position in the molecule
forming the molecule isocitrate.
48. CITRIC ACID CYLE OR KREBS CYLE
3. Isocitrate dehydrogenase catalyze the oxidation of isocitrate
forming the a-ketoglutarate, 5 C-molecule. The byproducts of this
reaction are NADH and CO2
49. CITRIC ACID CYLE OR KREBS CYLE
4. The next reaction is acted by a-ketoglutarate dehydrogenase
Wherein a-ketoglutarate loses its C02 and a coenzyme-A is added
in its place. The decarboxylation happens with the aid of NAD which
the becomes NADH. The resulting molecules is called succinyl-CoA.
50. CITRIC ACID CYLE OR KREBS CYLE
5. Succinyl-CoA is converted into succinate by the catalyzing of the
Succinyl-CoA synthase. Also in this reaction, a molecule of guanosine
triphosphate(GTP) is synthesized. The free phosphate group attacks the
Succinyl-CoA molecules resulting to the detaching of the CoA from the molecule.
51. CITRIC ACID CYLE OR KREBS CYLE
6. Succinate is catalyzed by succinate dehydrogenase leading to
The removal of 2 hydrogens. The molecules of Flavin Adeninde
dinucleotide(FAD)
, a coenzyme similar to NAD, is reduced to FADH2, as it takes the hydrogens
from succinate. This reactions produce the fumarate.
52. CITRIC ACID CYLE OR KREBS CYLE
7. Fumarate is then converted to malate as the enzyme fumarase
catalyzes the addition of water molecules.
53. CITRIC ACID CYLE OR KREBS CYLE
8. The final reaction is the regeneration of the oxaloacetate as the
enzyme malate dehydrogenase reacts with malate. The resulting
byproduct of this regeneration is NADH.
54. CITRIC ACID CYLE OR KREBS CYLE
9. Remember the two pyruvate were produce in glycolysis causing
the Krebs cycle to turn twice. Each turn produce 3 NADH, 1 ATP.
1 FADH, and the waste product CO2.
56. Oxidative Phosphorylation
In oxidative phosphorylation, an electron transport chain is coupled
with chemiosmosis to generate ATP.
-It occurs in the inner mitochondrial membrane of eukaryotes.
57. Oxidative Phosphorylation
-This stage uses the NADH and FADH2 produced from the first two stages.
-Electrons are accepted by NADH and FADH2, which act as transporters, in a
series of reactions before ATP is produced.
58. Electron Transport Chain
• NADH enters the chain at the NADH-Q reductase complex. FADH2 enters the
chain at the cytochrome reductase complex.
• It produces a proton gradient across the membrane which stores energy and
drives chemiosmosis.
59. Chemiosmosis
• ATP production is driven by the backflow of H+ in the gradient
across the mitochondrial membrane.
• ATP is produced from an enzyme called ATP synthase. The ATP
synthase enzyme works like a reverse ion pump for H+.
60. Chemiosmosis
• When the ATP synthase enzyme rotates, the diffusion of H+ to the inner
mitochondrial matrix couples with the bonding of ADP and an inorganic
phosphate to produce ATP.
• Electrons reach H+ and oxygen molecule to form water. This step is catalyzed
by cytochrome oxidase.
• O2 is the final electron acceptor in cellular respiration.
