Unit 2 Flashcards
Plant Cell
- cells in plants
- has chloroplast and cell walls
- eukaryotic
Animal Cell
- cells in animals
- eukaryotic
Prokaryote
- single cell organism
- doesn’t have a nucleus or membrane bound organelles
Ribosomes
- complexes of ribosomal RNA and protein
- do protein synthesis
Nucleus
- brain of the cell
- where all the dna is stored
- double membraned
Nucleolus
- in the nucleus
- supposed to make and assemble ribosomes
Nucleoid region of Prokaryotes
- where dna is found
- no membrane
- also has ribosomes and some proteins and RNA
mRNA
- messenger RNA
- used during protein synthesis
- single stranded
- read by a ribosome during protein synthesis
Smooth ER
- Synthesizes lipids
- Metabolizes carbohydrates
- Detoxifies drugs and poisons
- stores calcium ions
Rough ER
- Has bound ribosomes, which secrete glycoproteins (proteins covalently bonded to carbohydrates)
- Distributes transport vesicles, proteins surrounded by membranes
- Is a membrane factory for the cell
Golgi Apparatus
- made of flat sacs: cisternae
- does the correct folding and chemical modification of newly synthesized proteins
- does packaging for protein trafficking
Cell Compartmentalization
Separates areas from each other and specific functions are able to happen in each area
- ex. chloroplasts and mitochondria and nucleus (all double membraned)
Vesicle
- A small sac formed by a membrane and filled with liquid
- Vesicles inside cells move substances into or out of the cell
Mitochondria
- double membrane
- folds increase surface area = more ATP can be synthesized
- has cellular respiration, krebs cycle, electron transport, and ATP synthesis
Double membrane organelle
mitochondria, chloroplast, nucleus
Fatty Acids
building block for lipids
Hydrophobic
repels water
Hydrophilic
attracts water
Ionic
interaction of attraction between oppositely charge ions
Polar
molecule with a positively and negatively charged end
Non-polar
molecule that shares electrons equally and does not have oppositely charged ends
Ion
atom with a net charge
Protein Trafficking
proteins that are properly folded in the (ER) are transported to the Golgi via vesicles, forwarded to the trans-Golgi network (TGN) and then finally delivered to the plasma membrane (PM) or secreted to the extracellular space.
Lysosomes
- can digest macromolecules that can then be used by the cell
Hydrolytic enzymes
they break down large molecules into small molecules
Vacuole
help store waste in animals and water in plants
Chloroplast
- have double membranes
- contains pigments for photosynthesis
- carbon fixation happens there
Protein synthesis
- transcription: from dna to rna
- translation: the mRNA is decoded and creates the amino acid sequence
Apoptosis
a type of cell death that is programmed
turgor pressure
the force within the cell that pushes the plasma membrane against the cell wall.
thylakoids
They are the site of the light-dependent reactions of photosynthesis.
stroma
a fluid in chloroplasts
- where the light independent reactions happen of photosynthesis
grana
stacks of thylakoids
photosystems 1 and 2
- complexes of proteins and pigments to collect light energy
- ps2: light is absorbed here and then passed by pigements until it reaches the reaction center and the energy is transferred to ps1.. splits water and creates O2
- ps1: energy arrives and joins the pair of chlorophylls in reaction center, electron is boosted and then transferred to acceptor molecule. missing electron from chlorophylls is replaced by new electron from ps2
ps2 absorbs 680 wavelength, ps1 absorbs 700. ps2 gets new electrons from water, ps1 gets new electrons from the electron transport chain from ps2
photosynthesis
autotrophs use sun’s energy, CO2 and H2O to make glucose (C6 H12 O6) and oxygen
carbon fixation
- calvin cycle (light independent reactions)
happens in stroma of chloroplast
carbons atoms from CO2 are incorporated into organic molecules and used to make sugars
krebs cycle
is a series of chemical reactions that produce ATP as part of the metabolism of aerobic organisms. It takes place after glycolysis and is a key element of cellular respiration.
uses carbs as energy source
electron transport chain
a series of proteins and organic molecules found in the inner membrane of the mitochondria. Electrons are passed from one member of the transport chain to another in a series of redox reactions. Energy released in these reactions is captured as a proton gradient, which is then used to make ATP
ATP
energy source for cells
helps fuel the light independent reactions, and are created by the light dependent reactions
ADP
made of two phosphate molecules
usually converted into ATP
used for transferring energy
product of calvin cycle, later used for light dependent reactions
NADP+
a universal electron carrier
it can accept electrons and hydrogen atoms to create NADPH
product of calvin cycle, later used for light dependent reactions
NADPH
helps fuel the light independent reactions, and are created by the light dependent reactions
NAD+
NAD + is formed in aerobic respiration by a fermentation process and formed in anaerobic respiration by oxidation of NADH
NADH
molecules produced by the Krebs Cycle that go on to donate electrons in oxidative phosphorylation.
Surface Area
total area of each face
should be bigger than volume for it be more efficient
volume
base times height time depth
should be smaller than surface area to be more effective
surface area to volume ratio
- area to volume ratios affect ability to biosystem to get necessary resource, eliminate waste product, acquire or dissipate thermal energy and otherwise exchange chemicals and energy with the environment
plasma membrane
made of phospholipid bilayer
fluid mosaic model
In this model, a flexible layer made of lipid molecules is interspersed with large protein molecules that act as channels through which other molecules enter and leave the cell.
phospholipid
- used to make up membranes
- composed of a phosphate head and a fatty acid tail.
steroid
a family of lipids that have quite a different structure compared to fats and phospholipids.
- four fused hydrocarbon rings w/ various chemical that decides which kind of steroid
ex. cholestrol
The steroid hormones pass through the plasma membrane of a target cell and adhere to intracellular receptors residing in the cytoplasm or in the nucleus. The cell signaling pathways induced by the steroid hormones regulate specific genes on the cell’s DNA.
cholestrol
a component of the plasma membranes in animal cells, making it a vital part of cell structure – it helps keep membranes flexible and fluid. It is also the precursor to many other important steroids, such as the sex hormones
glycolipids
roles is to provide energy and serve as a marker for cellular respiration
glycoprotein
- act as receptors for molecules like hormones and pass on signals to the inside of the cell
selectively permeable membrane
A membrane which allows certain substances to pass, but does not allow others to pass through it
semi permeable membrane
thin bio sheets that allow cetain molecules to pass through them easier than others
channel protein
make an opening to transport, and doesn’t require any energy
diffusion/osmosis
- passive movement across membrane from high to low concentration
osmosis = diffusion of water
facilitated diffusion
- doesn’t require energy
- uses specialized proteins like channel and carrier proteins, helps move things across membrane
- in direction of concentration gradient
passive transport
does not require the cell to expend any energy and involves a substance diffusing down its concentration gradient across a membrane.
active transport
substances move against the concentration gradient, from an area of low concentration to an area of high concentration. This process is “active” because it requires the use of energy (usually in the form of ATP)
sodium potassium pump
- active transport that uses atp to move ions across membrane AGAINST the concentration gradient
membrane potential
the difference in electric potential between the interior and the exterior of a biological cell. It equals the interior potential minus the exterior potential.
cell wall
only in plants, some fungi and prokaryotes
separates the cells from outside and inside, and gives the plant cells structure
endocytosis
things enter into the cell through this process
has phagocytosis: takes in large particles and ingests other cells
and pinocytosis: takes in fluids and small molecules
exocytosis
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.
aquaporins
Aquaporins, also called water channels, are channel proteins from a larger family of major intrinsic proteins that form pores in the membrane of biological cells, mainly facilitating transport of water between cells.
concentration gradient
unequal distribution of molecules (eventually molecules move from high to low concentration)
water potential
Water potential is the tendency of water to diffuse from one area to another. Water molecules move from areas of high water potential to areas of low water potential by osmosis.
solute potential
= the negative ionization constant, molar concentration, pressure constant, and temperature in kelvin
- pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane
pressure potential
pressure exerted by the fluid (usually water) within the plant cell’s vacuole against the cell wall.
tonicity
Tonicity is the capability of a solution to modify the volume of cells by altering their water content. The movement of water into a cell can lead to hypotonicity or hypertonicity when water moves out of the cell.
eukaryotic cells
animal and plant cells
endosymbiosis
A symbiotic relationship where one organism lives inside the other
- resulted in the formation of the mitochondria and chloroplasts
