Term
|
Definition
Light Dependent
Light energy is captured and converted into chemical energy (ATP and NADPH).
Take place at thylakoid membrane. |
|
|
Term
|
Definition
Light Independent
ATP and NADPH are used to drive synthesis of carbohydrates.
Take place in stroma. |
|
|
Term
|
Definition
| Must eat food, organic molecules from their environment to sustain life |
|
|
Term
|
Definition
| Make organic molecules from inorganic sources |
|
|
Term
|
Definition
| Autotrophs that use light as a source of energy to make organic molecules |
|
|
Term
|
Definition
Semiautonomous organelles found in plant and algal cells that carry out photosynthesis. Contain large quantities of chlorophyll.
Outer, Inner, & Thylakoid membrane
Intermembrane Space
Stroma |
|
|
Term
| The majority of photosynthesis occurs in the ___________. |
|
Definition
| leaves (the internal part of the leaf is called mesophyll) |
|
|
Term
| Carbon dioxide enters and oxygen exits the leaf via pores called ______. |
|
Definition
|
|
Term
| Chlorophyll contained in ______________. |
|
Definition
|
|
Term
| 3 chemical products of light reactions |
|
Definition
|
|
Term
|
Definition
An energy intermediate
nicotinamide adenine dinucleotide phosphate
can accept 2 electrons
presence of additional phosphate grp (difference from NADH) |
|
|
Term
| Visible light detected by human eye |
|
Definition
|
|
Term
| In photosynthesis, ATP is regenerated by _________. |
|
Definition
|
|
Term
|
Definition
| regions of earth and atmosphere where living organisms exist |
|
|
Term
|
Definition
|
|
Term
|
Definition
type of electromagnetic radiation
travels as waves (shorter= more energy)
photons |
|
|
Term
|
Definition
1. pass through object (no change)
2. change path of light (no change)
3. object may absorb light (change) |
|
|
Term
|
Definition
| A molecule that can absorb light energy |
|
|
Term
| Light energy may be absorbed by _________________________________________. |
|
Definition
| boosting electrons to higher energy levels |
|
|
Term
|
Definition
| An electron that has absorbed energy |
|
|
Term
|
Definition
2 types: a & b
Both are bound to integral membrane proteins in the thylakoid membrane.
Porphyrin ring
Mg is bound to porphyrin ring
Delocalized electron (can absorb light energy)
Phytol tail
Long hydrocarbon structure, hydrophobic
Anchors pigment to the surface of proteins within the thylakoid membrane. |
|
|
Term
|
Definition
Type of pigment found in chloroplasts
Yellow -> Orange -> Red |
|
|
Term
|
Definition
Range & Efficiency
wavelengths are absorbed by different pigments |
|
|
Term
|
Definition
| Effectiveness to promote photosynthesis |
|
|
Term
| Pigment with maximum absorption spectrum? |
|
Definition
| Chlorophyll a (additional methyl grp than Chlorophyll b) |
|
|
Term
|
Definition
| Two distinct complexes of proteins and pigment molecules that capture light located in the thylakoid membrane. |
|
|
Term
| Light Dependent Reaction stages |
|
Definition
1. Primary Photoevent
2. Charge Separation
3. Electron Transport
4. Chemiosmosis |
|
|
Term
| Excited electrons are moved out of PSII by? |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
13 proteins
130 chlorophyll pigments
P700nm
functions 2nd |
|
|
Term
|
Definition
functions first
19 proteins
250 chlorophyll
P680 nm (more energy than 700)
P680->pheophytin->QA->QB |
|
|
Term
|
Definition
aka Cyclic Photophosphortylation
18ATP & 12 NADPH
electron cycling releases energy to transport H+ into lumen during synthesis of ATP. Ferrodoxin will not make NADPH because it has enough NADPH but not enough ATP. Takes electrons to QB. Never use PSII, no O2, no breakdown of H2O |
|
|
Term
|
Definition
electron begins at PSII and eventually transfers to NADPH
linear process produces ATP and NADPH equally (18ATP & 12 NADPH) |
|
|
Term
| Prokaryotic vs. Eukaryotic (Photosynthesis) |
|
Definition
| Prokaryotes only use PSI, only produce ATP (no O or NADPH), not as efficient |
|
|
Term
|
Definition
ATP and NADPH are used to make carbohydrates
inorganic C-> organic compound
direct production: glyceraldehyde-3-phosphate (NOT glucose) |
|
|
Term
|
Definition
1. Carbon Fixation
2. Reduction and Carbohydrate production
3. Regeneragtion of RuBP |
|
|
Term
| For every 6CO2 incorporated, ___ ATP and ___ NADPH are used. |
|
Definition
|
|
Term
|
Definition
6X RuBP-- +6X CO2--> 12X 3PG --> 12X 1,3-BPG --> 12X G3P (repeat)
10 G3P- regenerate Rubisco
2 G3P- make glucose by reverse glycolysis |
|
|
Term
|
Definition
90% of plants species on Earth
named because 3PG is a 3 carbon molecule |
|
|
Term
|
Definition
active site of Rubisco can also function as an oxygenase (but affinity for CO2 is 10fold than for O2)
when O2 is high and CO2 low, Rubisco adds O2 to RuBP
RuBP+O2--> 1X 3PG + Phosphoglycolate (2C) |
|
|
Term
|
Definition
minimizes photorespiration
mesophyll cells & bundle sheath cells
(3C)Phosphoenolpyruvate (PEP)--+CO2--> 4C Oxaloacetate by PEP Carboxylase (does not recognize O2=> minimizes photorespiration)
eventually enters Calvin cylcle |
|
|
Term
|
Definition
some C4 plants separate processes using time
Crassulacean Acid Metabolism
Stomata close at nigh
ex. cactus |
|
|
Term
| 2 reasons why cells need to respond to signals |
|
Definition
1. Need to respond to a changing environment
2. Cells need to communicate with each other |
|
|
Term
|
Definition
| Property (investigated by Darwin and son) that allows a plant to move towards light |
|
|
Term
|
Definition
| a signaling molecule transmitted from cell to cell and inhibited by the light |
|
|
Term
| Direct Intercellular Signaling |
|
Definition
Cell junctions allow signaling molecules to pass from one cell to another
Directly connected tissue |
|
|
Term
| Contact Dependent Signaling |
|
Definition
Some molecules are BOUND to the surface of cells and serve as signals to cell coming in contact with them.
No energy to move |
|
|
Term
|
Definition
| Cells secrete signaling molecules that bind to their OWN cell surface or neighboring cells of the same type. |
|
|
Term
|
Definition
Signal does not affect cell secreting the signal but does influence cells in close proximity (SYNAPTIC signaling)
LOCALIZED & SHORT-LIVED |
|
|
Term
|
Definition
| Signals (hormones) travel LONG distances and are usually LONGER-LASTING |
|
|
Term
| 3 stages of Cell Signaling |
|
Definition
1. Receptor Activation
2. Signal Transduction
3. Cellular Response |
|
|
Term
| Possible Cellular Responses |
|
Definition
Alter activity of 1 or more enzymes
Alter structural protein function
Change gene expression (transcription)
*NEVER Change gene EXPRESSION* |
|
|
Term
|
Definition
=signaling molecule
binds noncovalently to receptor
very specific
very rapid
causes conformational change |
|
|
Term
| Types of Cell Surface Receptors |
|
Definition
1. Enzyme-linked receptors
2. G-protein couples receptors (GPCR)
3. Ligand-gated ion channels |
|
|
Term
|
Definition
A cell surface receptor
Found in ALL living species.
Extracellular domain binds signal.
Present on plasma membrane.
Causes intracellular domain to become functional catalyst.
Most are protein KINASES (add or take Pi).
Has aa: serine, theorine, TYROSINE. |
|
|
Term
| G-protein couples receptors (GPCR) |
|
Definition
A cell surface receptor
Common in EUKARYOTES.
Protein has 7 TRANSMEMBRANE (pass/multipass) segments.
Activated receptor binds to G-protein.
Releases GDP (inactive) and binds GTP (active) instead.
GTP causes G-protein to disassociate.
a-subunit and B/y-dimer interact with other proteins in a signaling pathway. |
|
|
Term
| What happens when GPCR's signal is gone? |
|
Definition
| a-subunit recognizes loss and hydrolyzes GTP -> GDP + Pi which then breaks into a-GDP & B/y (inactive state) |
|
|
Term
| Is G-protein a transmembrane protein? |
|
Definition
| No, the receptor is a transmembrane protein. |
|
|
Term
| Ligand-gated ion channels |
|
Definition
A cell surface receptor
Found in plant AND animal cells
Ligand binding causes ion channels to open and ions to flow through membrane.
In animals: signals btwn nerve & muscle cells, btwn 2 nerve cells, Ca2+ uptake |
|
|
Term
|
Definition
More rare compared to cell surface receptors.
ex) Estrogen Rs are in nucleus. Estrogen-R dimer complexes bind to DNA to activate transcription
ex2) Auxin |
|
|
Term
|
Definition
An indirect transcription factor
1. Auxin binds to TIR1 in cytosol
2. Activated TIR1 enters nucleus and causes breakdown of a protein that inhibits several genes that are needed for cell division. These genes are then transcribed into mRNA, and the mRNA is translated into proteins that promote cell division. |
|
|
Term
| Transcription factors regulate _________________. |
|
Definition
| transcription of specific genes |
|
|
Term
|
Definition
A category of enzyme-linked receptors found in animals.
Recognizes various types of signaling molecules (ex. Growth factor).
EGF (Epidermal Growth Factor) stimulates epidermal cells to divide. |
|
|
Term
|
Definition
Signals binding to cell surface are 1st messenger.
Many signal transduction pathways lead to production of 2nd messengers.
RELAY information.
ex. cAMP, Ca2+, Diacyglycerol (DAG) , & inositol triphosphate (IP3) |
|
|
Term
|
Definition
cyclic adenosine monophosphate
adenylyl cyclase stimulate synthesis
can activate protein kinase A (PKA)
2 advantages: Signal Amplification & Speed |
|
|
Term
|
Definition
Extra Cellular Matrix
=proteins (strength) and polysaccharides (gel-like)secreted by exocytosis from ER form a complex meshwork outside of cells.
ex. bone, cartilage, woody part of plants |
|
|
Term
|
Definition
1. Adhesive
help cells adhere to ECM
ex. Fibronectin & Caminin
2. Structural
ex. Collagen & Elastin |
|
|
Term
|
Definition
Adhesive protein of ECM
connects |
|
|
Term
|
Definition
Adhesive protein of ECM
skin |
|
|
Term
|
Definition
Structual protein of ECM
provides tensile strength
found in bone, cartilage, tendon, skin |
|
|
Term
|
Definition
Structural protein of ECM
needed in ares taht expand and return to original shape
covalent cross links
ex. blood vessels |
|
|
Term
| Most abundant polysaccharide in animal ECM? |
|
Definition
glycosaminoglycans (GAGs)
-long, unbranched with repeating disaccharide unit
-highly negative charge attracts ions and water
-majority linked to core proteins to form proteoglycans |
|
|
Term
|
Definition
in plant cell walls
-develops btwn newly made cells
-flexible and allows for size increase
-main macromolecules:
1. cellulose (thick microfiber)
2. hemi-cellulose (think microfibers, any sugar BUT glucose)
3. glycans (branched polysaccharide)
4. pectins (charged polysaccharide, highly negative) |
|
|
Term
|
Definition
in plant cell walls
-layers of cellulose, lignin & other components
-more variable structure than primary cell wall |
|
|
Term
|
Definition
Proteins that allow cells of a certain tissue to be associated with each other.
adhere cells to each other and ECM
animal cells are more varied
plants' cellular organization is diff bc of rigid cell wall |
|
|
Term
| _____ activates PKA (protein kinase A). |
|
Definition
| cAMP (by binding to the regulatory subunits of PKA which release the catalytic subunits) |
|
|
Term
| Activate PKA phosphorlyzes ________ & ____________. |
|
Definition
| phosphorlyase kinase (inactive) & glycogen synthase (active) (both involved in metabolism of glycogen) |
|
|
Term
| ________ converts cAMP to AMP |
|
Definition
|
|
Term
|
Definition
| Signaling molecule binds to GPCR, then activates G-protein. Instead of activating adenylate cyclase (to make cAMP), the a subunit activates PHOSPHOLIPASE C. This breaks a covalent bond in a plasma membrane phopholipid with an inositol head group, producing DAG and IP3. |
|
|
Term
| IP3 binds a ligand-gated Ca2+ channel in ER membrane and causes? |
|
Definition
| the channel to open, releasing Ca2+ into the cytosol. Ca ions act as 2nd messengers now. Ca2+ can bind to PKC(which in combo with DAG, activates PKC) or bind to calmodulin |
|
|
Term
|
Definition
plants-phototropism, opening and closing of stomata, gravitropism
animals- nerve transmission, muscle contraction, secretion of digestive enzymes |
|
|
Term
|
Definition
heart muscle cells contraction
Ca store in sarcoplasmic reticulum
ca binds to troponin leading to muscle contraction
dropping ca causes muscle to relax
PHOSPHOLAMBAN activates Ca pump
activates adenylyl cyclase (prod. cAMP) |
|
|
Term
| cAMP activates PKA to phosphoylate _______ & ________. |
|
Definition
|
|
Term
| Ca concentrations in SER, cytosol, and outside of cell? |
|
Definition
|
|
Term
| Troponin has a lot of _______ receptors. |
|
Definition
|
|
Term
| Formation of Structural Proteins of ECM |
|
Definition
usually made in ER lumen in form of a-fibers (3a-fibers=pro-collagen, has extensions that prevent lengthening and increase thickness)
Pro-collagen secreted in vesicles, extensions dissolve, and pro-collagens combine. |
|
|
Term
| Anchoring Junctions (4 types & function?) |
|
Definition
-connect, hold, attach cells to each other and to ECM
-rely on Cell Adhesion Molecules (CAM) (cadherin & integrin)
1. adherins junctions
2. desmosomes
3. local adhesions
4. hemidesmosomes |
|
|
Term
|
Definition
A type of Anchoring Junction
CAM: Cadherin
Type of Adhesion: Cell to Cell
Cytoskeletal Protein: Actin |
|
|
Term
|
Definition
A type of Anchoring Junction
CAM: Cadherin
Type of Adhesion: Cell to Cell
Cytoskeletal Protein: Intermediate fibers |
|
|
Term
|
Definition
A type of Anchoring Junction
CAM: Integrin
Type of Adhesion: Cell to ECM
Cytoskeletal Protein: Actin |
|
|
Term
|
Definition
A type of Anchoring Junction
CAM: Integrin
Type of Adhesion: Cell to ECM
Cytoskeletal Protein: Intermediate fibers |
|
|
Term
|
Definition
-Cell to Cell junctions
-Major CAMs of vertebrates
-Dimer of identical subunits
-Extracellular domain of 2 cadherin dimers in adjacent cells bind to each other to promote cell-to-cell adhesion
-Inside cell, linker proteins connect cadherins to the cytoskeleton |
|
|
Term
|
Definition
-Transmembrane proteins
-group of cell surface receptor proteins
-extracellular domain for binding cell to ECM
-intracellular domain for binding to cytoskeleton |
|
|
Term
|
Definition
-or occluding junctions
-forms tight seal btwn adjacent cells
-prevents ECM from leaking btwn cells
-made by occludin & claudin (bind to each other to form tight seal, not mechanically strong, not bound to cytoskeleton) |
|
|
Term
|
Definition
cell adhesion
cell migration
cell growth |
|
|
Term
|
Definition
alter ability to bind to components in ECM
lowering/increasing affinity
cell adhesion
migration |
|
|
Term
|
Definition
aka communicating
-sm gap btwn plasma membrane of cells at junction
-6 connexin proteins in 1 cell align with 6 in an adjacent cell to form a connexon
-connexon allows passage of ions and sm molecules, sharing of metabolites & directly signal on each other |
|
|
Term
|
Definition
In plant cells
-Dont form cell-to-cell connections
-An additional component of ECM
-1st layer forms when cells dividing
-cement cell walls of adjacent cells together
-rich in PECTIN (ripening fruit secrete pectinases so that ripe fruit is less firm) |
|
|
Term
|
Definition
-functionally similar to gap junctions
-allow passage of ions, water, signaling molecules btwn cells
-diff bc they are open channels where the cell membrane of 1 cell is continuous with adjacent cell membrane
-desmotubule connects ER membrane of adj. cells |
|
|
Term
| Infections in plant cells move easily because of _________. |
|
Definition
| the desmotuble (plasmodesmata). |
|
|
Term
| _______ contain the genetic material. |
|
Definition
|
|
Term
| Chromosomes are composed of _________ & ________. |
|
Definition
|
|
Term
| Primary function of genetic material? |
|
Definition
| To store needed information |
|
|
Term
| __________ is the DNA-protein complex making up chromosomes. |
|
Definition
|
|
Term
|
Definition
|
|
Term
| the shortest choromosome? |
|
Definition
|
|
Term
| DNA wraps itself around _________. |
|
Definition
|
|
Term
|
Definition
11nm in diameter
A repeating unit of DNA wrapped around an octamer of histone proteins.
The negative charges of DNA are attracted to the positive charges of histones.
200 nucleotide base pairs |
|
|
Term
|
Definition
8 histone proteins + 146 nucleotide base pairs
H2- 2 copies
H2- 2 copies
H3- 2 copies
H4- 2 copies |
|
|
Term
| What brings nucleosomes closer together? |
|
Definition
|
|
Term
| DNA length would be ____. |
|
Definition
|
|
Term
|
Definition
very basic proteins
large number of positively charged lysine & arginine aa. (negative charge of DNA is attracted to this positive charge) |
|
|
Term
|
Definition
Matrix Attachment Region/ Scaffold Attachment Region
associated with histone linker protein that brings nucleosomes together to form 30 nm fibers. |
|
|
Term
|
Definition
Made when nucleosomes are organized into a more compact structure (shortens nucleosome structure by 7fold)
interact/anchored with the nuclear matrix
compacts 30nm fiber by formation of RADIAL LOOP domains |
|
|
Term
|
Definition
|
|
Term
|
Definition
| No they are located in discrete non-overlapping chromosome territory. Different chromosomes are not substantially intertwined even when non-compacted. |
|
|
Term
|
Definition
-HIGHLY compacted
-transcriptionally INACTIVE
-some localized regions in non-dividing cells
-radial loops (30 nm in range of 700nm) |
|
|
Term
|
Definition
-LESS condensed
-capable of GENE TRANSCRIPTION
-Most chromosomal regions in non-dividing cells
-radial loops (30nm in range of 300nm)
-LIGHTLY stained
-ALL euchromatin converted to heterochromatin when preparing to divide (most transcriptional activites cease during cell division) |
|
|
Term
|
Definition
-MAXIMUM compaction
-1400nm by condensin and cohesin (proteins)
-highly compacted radial loops remain anchored to a scaffold formed from proteins in the nuclear matrix
-when all euchromatin are converted to heterochromatin |
|
|
Term
|
Definition
=cell division in eukaryotes that requires a replication & sorting process that is more complicated
- cell divides to produce 2 new cells (daughters) genetically identical to the original (mother)
-plants: asexual reproduction
-animals:production & maintenance of multicellularity |
|
|
Term
|
Definition
|
|
Term
|
Definition
| 1n (gametes have 1 member of each pair) |
|
|
Term
|
Definition
|
|
Term
|
Definition
1. G1
2. S
3. G2
4. M
5. C
AKA cell cycle |
|
|
Term
|
Definition
|
|
Term
|
Definition
A cell in this phase has either postponed dividing or decided to never divide again
ex. nerve cells |
|
|
Term
|
Definition
1st gap
-cell prepares to divide
-accumulating nutrients to grow, etc
-reaches restriction point (can only go forward)
-maximum density
-takes the longest |
|
|
Term
|
Definition
synthetic
-chromosomes are replicated. the double strands unwind & copy
-at end of S, cell has twice as many chromatids as chromosomes in G1
ex. 46 chromosomes in G1-> 46 pairs of sister chromatids, 92 sister chromatin, 46 centromeres in S phase |
|
|
Term
| ___________ tell you how many chromosomes there were to begin with. |
|
Definition
|
|
Term
|
Definition
-Organelles DIVIDE
- cell prepares for genomic separation
-deposition of KINECTOCHORE around centromere
-microtubules begin to assemble
-chromosomes CONDENSE |
|
|
Term
|
Definition
-where mitosis occurs
-distributes the replicated chromosomes to the two daughter cells
(1. Interphase)
2. Prophase
3. Prometaphase
4. Metaphase
5. Anaphase
6. Telophase
(7. Cytokinesis) |
|
|
Term
|
Definition
1st phase of mitosis
-chromosomes start condensing
-nuclear membrane broken into vesicles
-nucleolus disappears
-microtubules formed by rapid polymerization of tubulin protein (3 types)
-mitotic spindle forms
-kinetochores begin to mature & attach to spindle |
|
|
Term
| 3 types of spindle microtubles |
|
Definition
formed in prophase but not functional until prometaphase
1. Aster (astral)
-imp for positioning of spindle apparatus
2. Polar
-help to push the poles away from each other
3. Kinetochore
-attach to the kinetochore, which is bound to centromere of each individual chromosome |
|
|
Term
|
Definition
-mitotic spindle completely formed
-centrosomes move apart
-spindle fibers interact with sisters
-2 kinetochores on each pair of sisters are attached to kinetochore microtubules from opposite poles |
|
|
Term
|
Definition
| pairs of sister chormatids ALIGN in a single row |
|
|
Term
|
Definition
sister chromatids are pulled towards poles
-poles move apart
-centromeres move toward poles |
|
|
Term
|
Definition
aka reverse prophase
-spindle disassembled
-nuclear envelope forms around each set of sisters |
|
|
Term
|
Definition
-cleavage of cell into 2 halves
animal cells: constriction belt of actin filaments, cleavage furrow, constricts like drawstring
plants: cell plate grows outward, space between cells get pectin (middle lamella) |
|
|
Term
| Cyclins/Cyclin-dependent kinases (cdks) |
|
Definition
-responsible for advancing a cell through the phases of the cell cycle
-3 checkpoints (G1/restriction point, G2, & Metaphase) |
|
|
Term
|
Definition
=sexual reproduction requires a fertilization event in which two haploid gametes unite to create a diploid cell called a zygote
-process by which haploid cells are produced from a cell that was originally diploid
-begins after interphase |
|
|
Term
| 3 key differences between Meiosis and Mitosis |
|
Definition
1. Homologous pairs form a bivalent/tetrad (synapsis)
2. crossing over
3. reduction division |
|
|
