AP Bio Unit 3: Energy Transformations and Mitosis

Thylakoids

Membrane bound structure, play a vital role in photosynthesis

Stroma

Dense fluid found within the chloroplasts surrounded by an envelope of 2 membranes

Grana

Stacks of thylakoid sacs found within chloroplasts

Chlorophyll

A green pigment located in membrane within the chloroplasts of plants and algae

Electron transport proteins

Facilitate the transfer of electrons from electron donors like NADH and FADH, to oxygen

Photosystems

A light capturing unit located in the thylakoid membrane, consists of a reaction center complex surrounded by numerous light-harvesting complexes

Light-dependent reactions

Initial phase of photosynthesis, photosystem 1 and 2, reactions produce ATP and NADPH, which are essential for the Calvin cycle

Carbon fixation

Where organisms convert inorganic carbon(co2) into organic carbon compounds (glucose) , 1st stage of the Calvin cycle

Calvin cycle

2nd stage of photosynthesis, happens in the stroma of chloroplasts, 3 main phases, carbon fixations, reduction and regenerations of Co2 acceptor

Krebs cycle (citric acid cycle)

Complete energy-yielding of organic molecules, 8 steps, generates ATP and transfers most chemical energy to NAD+ and FAD

Matrix

The supportive, non cellular substance in tissues, internal environment of organelles

Surface area to volume ratio

As the cell grows, its volume increases faster than cells surface area, larger cells have a lower SA relative to their volume

Second law of thermodynamics

Every energy transfer increases the disorder of entropy of the universe

ATP

Crucial molecule for energy transfer increases cells, ATP is regenerated from ADP and phosphate, ATP hydrolysis alters protein shapes, ATP energy is used for cellular work

ADP

Forms ATP when added to phosphate group

NADPH

Crucial molecule in light reactions, NADPH comes from the reduction of hydrogen ions and NAPH+, acts as a source of electrons

Electrons

Subatomic particles with a negative charge

Electrochemical gradient

Combined affect of electrical and chemical forces that drive ion movement across cell membranes

Proton

Subatomic particle with a positive charge

ATP synthase

Synthesizers ATP from ADP and inorganic phosphate using energy from a proton gradient

Alcoholic fermentation

Glucose converted into ethanol and CO2, anaerobic

Lactic acid fermentation

Where private is reduced by NADH to form lactate without releasing CO2, regenerates NAD+, allowing glycolysis to continue

Aerobic respiration

Cellular processes that efficiently converts glucose into energy, glycolysis, citric acid cycle and oxidative phosphorylation

Anaerobic respiration

Allows cells to produce ATP without oxygen

Chemiosmosis

Energy from a proton gradient, built by the ETC, drives the synthesis of ATP through ATP synthase

Oxidative phosphorylation

Important process in cellular respiration, inner membrane of mitochondria, contains ETC and chemiosmosis

Photophosphorylation

Process of generating ATP and ADP and phosphate during light reactions of photosynthesis, ETC and ATP synthase and photosystems, this process transforms light energy to chemical energy

Endothermic organism

Mammals and birds, maintains body temperature primarily through heat generated by their own metabolism, allows us to keep a stable body temperature even through external environment is changing

Glycolysis

Breaks down glucose into pyruvate molecules and yields energy, occurs in the cytosol, glucose is phosphorylated using 2ATP molecules and converts them to 2 ADP and 2 phosphate groups

Glucose

6 carbon sugar that plays a crucial role in cellular respiration

Pyruvate

Ke junction in the pathways of glucose oxidation and end product of glycolysis

Interphase

Critical phase of cell cycle where the cell prepares to divide, precedes mitosis, cell grows and DNA replicates

G1 phase

Initial phase of interphase, the cell undergoes significant growth and metabolic activity, produces proteins and organelles

S phase

Where DNA replication occurs, the cell duplicates its chromosomes, ensuring each daughter cell receives an identical set of genetic material

G2 phase

Final part of interphase in the cell cycle, the cell continues to grow and prepare for division, also include metabolic activity

G0 phase

Non dividing state that cells enter when they do not receive that go-ahead signal at the G1 checkpoint

Genome

A complete set of DNA in an organism

Asexual reproduction

Involves a single parent producing off spring that are genetic clones of themselves

Cell cycle

Fundamental process that ensures the continuity of life by allowing cells to divide, grow and pass genetic information from parent to child

Prophase

Chromosomes pair up, crossing over of genes, chromosome condense, spindle formation, nuclear envelope breaks down

metaphase

Chromosomes line up at the metaphase plate (middle)

Anaphase

Chromosomes are separated and moved to opposite poles of the cell, separation of sister chromatids, ensures that each daughter receives and identical set of chromosomes

Telophase

Final stage of mitosis, results in 2 daughter cells, chromosomes begin to uncoil, nuclear envelope starts to reform

Checkpoints

Gates or stop signs to see if cells are ready to move on with division or not

Cyclins

Proteins that initiate interphase and when levels are high, the CDK attaches

Cyclin dependent kinases

Responsible for phosphorylation specific target proteins, which changes their activity and drives the cell cycle forward

Cancer

Disease characterized by uncontrollable cell division, cancer cells bypass the checkpoints

Haploid

Cell that has one pair of chromosomes

Diploid

A cell that has two sets of chromosomes

Growth factors

Proteins released by certain cells that stimulate other cells to divide

Photosystem 2

Photons of light hit chlorophyll then the electron gets excited and gets passes to an electron carrier

Photosystem 1

Photons of light hit chlorophyll in photosystem 1 and excite electrons and then get passes to an electron carrier