Unit 1 Flashcards
What is life?
Living things are composed of cells, have different levels of organization, they use energy, respond to their environment, grow, reproduce and adapt to their environment.
8 characteristics of living: cellular organization, reproduction metabolism, homeostasis, heredity, responds to stimuli, growth and development, and adaptation through evolution
3 Scientists discoveries in spontaneous generation
- Aristotle → his belief was that living organisms could come from non-living things. Ex) decaying meat became maggots
- Francesco Redi → He was an Italian physician who tried to prove that maggots come from files and not decaying meat
- Louis Pasteur → He opposed the idea of spontaneous generation. He believed micro-organisms come from cells called spores. He tested his hypothesis through the use of an infusion of nutrients in a swan necked flask
Biogenesis
The theory of biogenesis states that all organisms are produced from other organisms
3 Abiogenesis
- Miller + Urey - This experiment was one of the first to prove it was possible to generate organic compound’s from inorganic sources. Can create organic compounds when energy is added
- Margulis - Discovered that some organelles like mitochondria and chloroplasts originated as bacteria (ENDOSYMBIOSIS)
- Endosymbiosis - a symbiotic relationship where one organism lives inside the other. Refers to the original internalization of prokaryotes by an ancestral eukaryotic cell, resulting in the formation of the mitochondria and chloroplasts
3 parts of the cell theory
- All living things are made up of cells
- unicellular → composed of one cell only
- multicellular→ composed of many cell that may organize into tissues → organs →organ systems - Cells are the basic unit of life
→ smallest part of an organism that is capable of all life’s processes
→ make up all living things (Anamalia, Plantae, Protista, etc.) - All cells come from other cells
→ similar to biogenesis and the idea that all living things come from something else living
Prokaryotic vs. Eukaryotic
- Prokaryotic → They do not contain a nucleus, they do not have a membrane bound organelles, cell division is done through binary fission, they are unicellular, they contain cell walls made of peptidoglycan. Organisms with this type of cell are bacteria
- Eukaryotic → They contain a nucleus, they contain membrane bound organelles, cell division is done through mitosis, they can be uni or multicellular. Only fungi plants have cell walls, which are made up of chitin or cellulose
Ex) animals, plants, fungi, und protists
Phospholipid Bilayer
It is a special type of organic molecule. It has a head where the phosphate groups and a tail where the fatty acid chain is. The head is hydrophilic and the tail is hydrophobic. Bilayer is composed of two phospholipids that line up tail to tail. Proteins allow certain things to pass through the cell membrane
3 Parts of the Cell Wall
- Bacteria → The cell walls are composed of peptidoglycan
- Fungi → The cell walls are made up of chitin
- Algae → Typically has cell walls made of glycoproteins & polysaccharides
What is the Cell Wall?
The cell wall is the protective semipermeable outer layer of certain organisms. It’s main function is to give the cell strength and structure, and to filter molecules that passing and out of the cells
2 Types of Transport
→ Passive Transport: Does not require energy - from high to low concentration
* Diffusion - movement from high to low concentration gradient
* Osmosis - movement of H20 from high to tow concentration gradient
→ Active Transport: Requires ATP energy - from low to high concentration
* Exocytosis - exiting the cell
* Endocytosis - entering the cell; Pinocytosis-liquids, Phagoctosis-solid
Chemical Equation for Photosynthesis
6C02 + 6H20 → C6H12O6 + 6O2
3 Parts of the Chloroplast
- Stroma - Aqueous substance/surrounding thylakoids containing enzymes for the dark reaction / Calvin Cycle
- Thylakoids - Structure containing chlorophyll pigments and enzymes for light reactions (looks like stack’s of coins)
- Grana - a singular stack of thylakoids
Process of Light Dependent Reaction
Takes place in the thylakoid, requires light energy, chlorophyll absorbs light energy, energy is transferred to photons and they get excited. Reaction starts in PSII, H2O splits apart, energy moves down the ETC through the cytochrome complex. Moves to PSI and photons re-excite electrons. ATP synthase occurs using the extra hydrogens to create ATP energy. NADPH is also created.
Process of Calvin Cycle
- 3 Steps:
- Fixation - 3xCO2 react RuBisCo catalyst with 3xRuBP = 6x 3PGA
- Reduction - 6x 3PGA use 6xATP & 6xNADPH =6xG3P
- 1xG3P become sugar/starch; 5xG3P use 3ATP = 3RuBP
- Repeats all again*
How are the 2 reaction related? (Light & Calvin)
The light reaction is the initial stage of photosythesis, which traps light energy to produce ATP + NADPH. Where as the dark reaction is the second step of photosynthesis which utilizes the energy from ATP + NADPH to produce glucose