C7: Cellular Metabolism Flashcards
It is a set of chemical reactions that occur in living organisms in order to maintain life.
Cellular Metabolism
involves complex sequences of controlled biochemical reactions, better known as metabolic pathways.
Cellular metabolism
is largely defined by the complex array of biochemical reactions involving bio- molecular synthesis (anabolism), maintenance, or breakdown (catabolism), the sum total of which define the energetic status of the cell.
Cellular metabolism
Mitochondria obtain the energy by ___ the substrates of the ___
oxidizing; Krebs cycle
It is a smooth unlike the inner membrane and has almost the same amount of phospholipids as proteins.
Outer (mitochondrial) membrane
Outer membrane of mitochondria has a large number of special proteins called ___.
porins
The ___ is completely permeable to nutrient molecules, ions, ATP, and ADP molecules.
outer membrane
The ___ is more complex in structure than the outer membrane as it contains the complexes of the electron transport chain and the ATP synthetase complex.
inner membrane
Inner membrane is permeable only to (3)
oxygen, carbon dioxide and water
It is made up of a large number of proteins that play an important role in producing ATP, and also helps in regulating transfer of metabolites across the membrane.
inner membrane
inner membrane has in- folding’s called the ___ the surface area for complexes and proteins that aid in the production of ATP, the energy rich molecules.
cristae
a complex of enzymes that are important for the synthesis of ATP molecules, special mitochondrial ribosomes, tRNAs and the mitochondrial DNA.
MITOCHONDRIAL MATRIX
FUNCTION OF MITCHONDRIA (9)
1.Energy Production
2. Cellular Respiration
3.Oxidative Phosphorylation
4. Krebs Cycle
5.Electron Transport Chain
6.ATP Synthase
7.Apoptosis Regulation
8.Calcium Signaling
9. Metabolism and Biosynthesis
Where does it occur?
-Cell respiration:
-Oxidative phosphorylation:
-Krebs cycle:
-Cell respiration: within mitochondria
-Oxidative phosphorylation: inner mitochondrial membrane
-Krebs cycle: mitochondrial matrix
proton gradient drives ATP synthesis through a process called ___
oxidative phosphorylation
It further breaks down molecules derived from nutrients, releasing electrons and generating molecules that enter the electron transport chain.
tricarboxylic acid (TCA) cycle
This series of protein complexes in the inner mitochondrial
membrane accepts electrons from the breakdown of molecules in the Krebs cycle. As electrons pass through the chain, protons are pumped across the membrane, establishing the proton gradient.
Electron Transport Chain
harnesses
the energy from the proton gradient to convert adenosine diphosphate (ADP) into ATP
ATP synthase
a nutrient needed by the human body for growth and maintenance.
protein
small loops of DNA found within mitochondria
Mitochondrial DNA
Contributes to determining the ancestry of various human groups and the early migration patterns of humans around the world.
HUMAN MITOCHONDRIAL DNA
claims that the human species had its origin in Africa about 250,000 years ago, then spread across the world
OUT-OF-AFRICA THEORY
out-of-africa theory is opposed by _____ which states that different human races around the world evolved independently from hominid precursors
Multiregional Theory
This technique provides evidentiary results and can also reveal lineage through the maternal line of a person or species
MITOCHONDRIAL DNA ANALYSIS
An umbrella term used to refer to a family of conditions caused by disorders which involve the mitochondria
MITOCHONDRIAL MYOPATHY
examples of MITOCHONDRIAL MYOPATHY (3)
Myoclonus epilepsy with ragged-red fibers,
Kearns-Sayre Syndrome,
Mitochondrial encephalomyopathy with lactic acidosis and Stroke-like episodes (MELAS)
A collection of genetic information carried in the mitochondria
MITOCHONDRIAL GENOME
Mitochondrial genome is inherited solely from the ___, which use for tracking generational changes, relationships, and inheritance. However, it has __ mutation rate when compared to ___ genome.
mother; high; chromosomal
The term can mean either the inner or the outer membrane of a mitochondrial cell,
mitochondrial membrane
The ___ of a mitochondrion is smooth and surrounds the entire organelle
outer membrane
the ___ mitochondrial membrane forms the cristae, a twisted, turning pathway resembling the folds of a brain.
inner
Organisms with complex, membrane-based cellular structures, including plants, animals, and humans, are known as __
eukaryotes
Under high-power magnification, mitochondria present as oval or oblong in shape, with a double membrane and an inner area known as the ___
matrix
Its the job of mitochondria to perform ____, the process of turning oxygen and nutrients into ATP.
aerobic respiration
: the ___ mitochondrial membrane helps in the production of ATP,
inner
___ mitochondrial membrane serves as a filter. Using a protein called __
outer; porin
It converts biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.
cell respiration
The reactions involved in respiration are ___, releasing energy in the process, as we so-called “high-energy”
catabolic reactions
Respiration is one of the key ways a cell releases chemical energy to fuel cellular activity. It is considered an ____
exothermic redox reaction
The overall process can be distilled into three main metabolic stages or steps:
glycolysis, the tricarboxylic acid cycle and oxidative phosphorylation
glycolysis also known as
Embden-Meyerhof-Parnas pathway -
First stage of cellular respiration, and it occurs in the cytoplasm of the cell.
glycolysis
During glycolysis, one molecule of ___ (a six-carbon sugar) is broken down into two molecules of __ (a three-carbon compound).
glucose; pyruvate
By products of glycolysis are , (3)
pyruvate, ATP, and NADH
Energy released during the breakdown of glucose and other organic fuel molecules from carbohydrates, fats, and proteins during glycolysis is captured and stored in ____.
ATP
The compound nicotinamide adenine dinucleotide (NAD*) is converted to NADH during this step.
Glycolysis
Pyruvate molecules produced during glycolysis then enter the mitochondria, where they are each converted into a compound known as _____ which then enters the TCA cycle.
acetyl Coenzyme A (pyruvate oxidation),
The overall process of glycolysis results in the following events: (3)
Glucose is oxidized into pyruvate.
NAD+ is reduced to NADH.
ADP is phosphorylated into ATP.
plays a central role in the breakdown, or catabolism, of organic fuel molecules.
Tricarboxylic acid cycle
The cycle is made up of eight steps catalyzed by eight different enzymes that produce energy at several different stages
Tricarboxylic acid cycle
Most of the energy obtained from the TCA cycle, however, is captured by the compounds __ and ___and converted later to ATP
NAD+; flavin adenine dinucleotide (FAD)
The products of a single turn of the TCA cycle consist of ___ molecules, which are __ (through the process of adding hydrogen, H) to the same number of NADH molecules, and one FAD molecule, which is similarly reduced to a single FADH, molecule.
three NAD+; reduced
These molecules____ go on to fuel the third stage of cellular respiration, whereas ___, which is also produced by the CA cycle, is released as a waste product.
molecules: FAD, NAD+
carbon dioxide
Acetyl-CoA combines with ___ to form citrate. Step __
oxaloacetate;
Step 1
Citrate is converted to ___. Step __
isocitrate;
Step 2
Isocitrate is __ to ___, releasing one molecule of ___ and one molecule of NADH. Step __
oxidized; alpha-ketoglutarate; carbon dioxide; STep 3
Alpha-ketoglutarate is converted to ___, releasing one molecule of ___ and one molecule of ___. Step __
succinyl-CoA; carbon dioxide; NADH; Step 4
Succinyl-CoA is converted to ___, with the transfer of the ___ to GDP to form GTP. Step __
succinate; CoA group;
Step 5
Succinate is ___ to __, releasing one molecule of ___. Step __
oxidized; fumarate; FADH
Step 6
Fumarate is __ to form __. Step __
hydrated; malate; Step 7
Malate is ___ to __, releasing one molecule of ___. Step __
oxidized; oxaloacetate; NADH
Step 8
each pair of hydrogen atoms removed from NADI and FADH, provides a pair of electrons that -through the action of a series of iron-containing hemoproteins, the cytochromes eventually reduces one atom of oxygen to form water.
Oxidative Phosphorylation
is the major mechanism by which the large amounts of energy in foodstuffs are conserved and made available to the cell.
Oxidative phosphorylation
The series of steps by which electrons flow to oxygen permits a gradual lowering of the energy of the electrons
Oxidative phosphorylation
This part of the oxidative phosphorylation stage is sometimes called the
electron transport chain.
Site of photosynthesis; Highly dynamic; influenced by environmental factors; contains its own DNA
chloroplast
Chloroplast Can also be found in other photosynthetic organisms, such as ___
algae and cyanobacteria
chloroplast are Commonly found in ___ located in plant cells
guard cell
Guard cell swollen:
Guard cell shrunken:
Guard cell swollen: stoma open
Guard cell shrunken: stoma closed
immature, undifferentiated cells; can only develop into chloroplast in the presence of light
protoplastids
double-membrane-bound organelles found in plant and algal cells; thought to have evolved from photosynthetic bacteria that were engulfed by eukaryotic cells billions of years ago.
protoplastids
Three types of protoplastids
chloroplast
chromoplast
leucoplast
are the green plastids that are responsible for photosynthesis
Chloroplasts
They contain carotenoids.
chromoplast
Colorless plastids
leucoplast
Photosynthetic pigment - Absorbs light energy for photosynthesis
chlorophyll
: widely distributed, abundant in green, initiates photosynthesis, converts light energy into chemical energy
1.Chlorophyll a
abundant in green, accessory pigment
Chlorophyll b:
found in protists and cyanobacteria
3.Chlorophyll c and d:
STRUCTURES OF CHLOROPLAST (7)
Thylakoid
Membrane Envelope
Intermembrane Space
Lumen
Granum
Stroma
Stroma Lamellae
- Extensive system of internal membranes that made up chloroplast Site of conversion of light energy to chemical energy
Thylakoid
- Contains inner and outer lipid bilayer membrane Inner membrane separates the stroma from the intermembrane space and regulates passage of molecules into and out of the chloroplast
Membrane Envelope
- Space between the outer and inner membrane
Intermembrane Space
- Compartment within each thylakoid
Lumen
Nutrients that are commonly used by animal and plant cells in respiration include __, ___, and __
sugar, amino acids, fatty acids
The most common oxidizing agent (electron acceptor) is .
molecular oxygen (O2)
Densely layered stacks of thylakoid (10 to 20) - Serves as site of conversion of light energy to chemical energy
granum
Dense fluid within the chloroplast that lies inside the envelope but outside of thylakoid membrane
stroma
Site of conversion of carbon dioxide to carbohydrates
stroma
Provide a structural framework for the chloroplast - Increase the surface area of the thylakoids
stroma lamellae
Contain Photosystem I and chlorophyll
Stroma lamellae
2 STAGES OF PHOTOSYNTHESIS REACTION
1.LIGHT DEPENDENT REACTIONS
2. CARBON FIXATION REACTION
“photo” part: ___
“synthesis” part: ____
“photo” part: LIGHT DEPENDENT REACTIONS
“synthesis” part: CARBON FIXATION REACTION
•: units where chlorophyll molecules and accessory pigments are organized with pigment-binding proteins
ANTENNA COMPLEX
: where light energy are transferred as each antenna complexes absorbs light
REACTION CENTER
• links PI and PII
ELECTRON TRANSPORT CHAIN:
: forms channels through which accumulate H+
ATP SYNTHASE
•: difference in the concentration of H+ between thylakoid lumen and stroma
PROTON GRADIENT
•3 ELECTRON CARRIERS:
1.Plastoquinone 2.Cytochrome B Complex 3.Plastocyanin
principal raw material for photosynthesis
H2O and CO2
Light dependent reaction
REACTANTS: 3
PRODUCTS: 3 types + quantity
REACTANTS: H2O, NADP, ADP
PRODUCTS: 3 ATP, 2 NADPH, 2 O2
a complex but essential process that plays a vital role in photosynthesis and life on Earth. - also known as the light-independent reactions of photosynthesis
Calvin cycle
A series of chemical reactions that use carbon dioxide from the air and energy from ATP and NADPH to produce glucose
calvin
calvin cycle takes place in
stroma
end products of Calvin
SUGAR, ADP, NADP+, Pi
