2.7 Plant Cells And Energy Production Flashcards
Autotrophs
Produce food from substances in their external environment such as light to generate ATP
Heterotrophs
Can’t produce their own food and use obtain nutrition form other organisms
Energy carrying molecules used by plants in photosynthesis
Nicotinamide adenine dinucleotide phosphate (NADPH) and ATP
ATP structure
Ribose with attached adenine and 3 phosphate group
Photosynthesis
Ability of plants to convert carbon dioxide into glucose and oxygen using sunlight
6CO_2 + 6H_2O —> C_6H_12O_6 + 6O_2
RuBisCO
Ribulose bisphosphate carboxylase
RuBP
Ribulose 1,5bisphosphate
G3P
Glyceraldehyde 3-phosphate
Most important determinants on rate of photosynthesis
- Light-intensity (more=faster until peak)
- Amount of carbon dioxide present (more=faster until peak)
- Temperature (higher=faster to a point but then rate declines if too hot)
Energy carrying molecules used by plants in cellular respiration
- Adenosine triphosphate (ATP)
- Nicotinamide adenine dinucleotide (NAD)
- Flavin adenine dinucleotide (FAD)
Cellular respiration
Process that converts the energy stored in NADH and FADH2 into ATP
Aerobic respiration
Uses oxygen as a reactant to produce energy
1 glucose + 6O_2 produces 38 ATP, 6CO_2, and 6H_2O
Anaerobic respiration
Turns glucose into energy (ATP or other energy-carrying molecules in the absence of oxygen. Produces lactic acid or ethanol.
AKA fermentation
Primary products of aerobic respiration
Carbon dioxide and water
Steps of aerobic cellular respiration
- Glycolysis
- Pyruvate oxidation
- Kreisler cycle (citric acid cycle)
- Electron transport chain
Glycolysis
Glucose undergoes a series of chemical transformations in which it is converted to 2 pyruvate molecules and yields a net of two ATP molecules
Pyruvate
Three-carbon molecule that is a product of glycolysis
Acetyl CoA
Product of Pyruvate being split into a two-carbon molecule and binding to coenzyme A. the carbon that is lost combines with oxygen to produce carbon dioxide as a waste product.
CoA
Coenzyme A
Carries pyruvate to the mitochondria where it is transformed into acetyl CoA to begin the Kerbs cycle
Electron transport chain (in aerobic respiration)
High energy electrons are released from NADPH and FADH_2 to generate more ATP. Most of ATP is produced during this stage.
ATP Synthase
Makes use of the hydrogen ion (proton) gradient created by the other parts of the electron transport chain to form ATP from ADP and a free phosphate group
Total energy production of aerobic cellular respiration
38 molecules of ATP per molecule of glucose
Role of oxygen in electron transport chain
Collects electrons at the end of the chain and combine them with hydrogen ions to make water.
In the absence of oxygen the ETC becomes saturated with e- and backs up the process down to the Krebs cycle
Fermentation
A form of anaerobic respiration in which energy is extracted through glycolysis
Lactic acid fermentation
Instead of pyruvate entering Krebs cycle, the e- released by gylcolysis are added to the pyruvate to produce lactic acid.
Cell growth
The process by which cells grow in size
OR
The process by which cells reproduce to increase in number
Gamete
A type of sex cell that has half of the normal DNA found in a somatic cell
Somatic cell
Body cell
Fertilization
Combining of two gametes
Zygote
Result of fertilization, develops into an embryo
Sexual reproduction
Requires two parent organisms or cells. Offspring not identical to parent cells but shares characteristics with each
Asexual reproduction
Does not requires two parent organisms or cells. Offspring genetically identical to parent.
Binary fission
Single parent cell doubles its existing DNA, replicates its internal structures, and divides into two cells. Common in bacteria.
Budding
Occurs when a small growth found on a parent organism spits off and continues growing on its own. Common in yeast.
Fragmentation
Occurs when an existing organism breaks into two or more fragments, which develop into new individuals. Common in plants and some marine animals such as coral, sponges, and sea stars.
Parthenogenesis
Occurs when an embryo develops from an unfertilized cell. Common in fish, amphibians, and reptiles.
Parent cell
The original cell that divides during cell division
Daughter cell
Two are produced by the parent cell during cell division
Cell cycle
Series of events that lead to the duplication of the DNA in the cell and the subsequent division of that DNA and the cytoplasm to produce two daughter cells
Meiosis
Cell division that results in four genetically distinct cells each with half the number of chromosomes of the parent cell.
Involved in sexual reproduction only
Mitosis
Cels division that results in two cells that are genetically identical and have the same number of chromosomes as the parent cell
Primarily involved in the growth and maintenance of organism systems and asexual reproduction
Chromosome
Consists of two identical chromatids called sister chromatids bound together by a centromere
Interphase (S) stage
The time when the cell isn’t dividing but may be growing and replicating DNA
Has three phases including
- G1 phase (first gap)
- S phase (synthesis of DNA)
- G2 phase (second gap)
Precedes mitotic (M) phase
Mitotic (M) phase
Relatively short phase that includes
- prophase
- metaphase
- anaphase
- telophase
Prophase
Step 1 of the Mitotic Phase
The cell has no nuclear envelope and prepares to divide by tightly condensing its chromosomes which pair up
- spindle fibers emerge and chromosomes condense, becoming visible
- the nucleolus disappears
- the nuclear envelope breaks down
Metaphase
Step 2 of the Mitotic Phase
Cell begins to elongate and chromosomes line up along the center of the cell
- mitotic spindle fully developed and centrosomes form at opposite poles of the cell
- chromosomes line up at the metaphase plate
- sister chromatids attach to the spindle fiber
Anaphase
Step 3 of the Mitotic Phase
Cell continues to elongate and the chromosomes are pulled apart
- sister chromatids break down
- chromosomes (formerly sister chromatids) move toward poles of the cell
- a cleavage furrow starts to appear
Telophase
Step 4 of the Mitotic Phase
Cell develops a nuclear envelope and begins to pinch in the middle
- chromosomes start to form a normal, jumbled arrangement
- a nuclear envelope surrounds the chromosomes
- the mitotic spindle breaks down
G1 phase
Cell accumulates the building blocks necessary to duplicate the chromosomes
S phase
DNA replication occurs and sister chromatids are created. They are held together by two centrosomes to make a mitotic bundle that facilitates chromosome movement
G2 phase
Cell accumulates necessary materials for the movement of chromosomes, duplicating important organelles. In this phase the cell may grow.
Cytokinesis
Division of the cytoplasm of a parent cell to form two new cells. Starts in anaphase and ends shortly after telophase
Diploid
Cell that has two sets of chromosomes
Haploid
Cell with a single set of chromosomes
Meiosis I
Number of chromosomes is halved
Consists of
- interphase I
- prophase I
- metaphase I
- anaphase I
- telophase I
Meiosis II
Generates two more haploid daughter cells from duplicated sister chromatids present in the daughter cells of meiosis I
Interphase I
Occurs before meiosis I
Very similar to interphase the precedes mitosis
