Unit 1- The working cell Flashcards
S1 S2 S3 Important Biological Molecules, Cell membrane structure and transport, Specialized cell-cell junctions
How are large biological molecules built and broken?(name the components) and Why broken down this way?
1) not made or broken down all at once, they’re made of smaller pieces called MONOMERS
2) large bio. molecules made or many monomers linked together are called POLYMERS
3) less complicated to pre-synthesize small molecules (or obtain them from the diet) and just attach/detach them
Name and describe the process in which large bio. molecules are built
almost always done by dehydration synthesis; building polymers by removing water from between 2 monomers
Name and describe the process in which large biological molecules (polymers) are broken
- by hydrolysis
- water is added to break the chemical bond between 2 monomers
Name 4 main types of cell-cell junctions
- Desmosomes
- Tight junctions
- Gap junctions
- Plasmodesmata
Describe desmosomes and their function
- junctions that attach and hold adjacent cells together
- prevent tearing of tissues under physical stress
Describe tight junctions and their function + where
- they hold the membranes of the two adjacent cells very close
together - they create a leak-proof seal
-they can be found in stomach,bladder, BBB (blood brain barrier)
name the 4 uses of lipids in nature
- insulation from cold
- energy storage
- hydrophobic barrier
- hormones for cell signaling
name the 5 general functions of cell membranes (SARRA)
- Selectively isolate the cell’s internal contents from its external environement
- Attaching cells together
- Regulate the exchange of materials between the inside/outside of the cell or organelle
- Regulate biochemial reactions
- Allow for communication with other cells
Name the 4 levels of protein structure
→ Because of the huge variety of amino acids, proteins can have very complex structures.
- primary structure (the simplest)
- secondary structure
- tertiary structure
- quaternary structure (most complex)
Name + name the function of ATP with 3 statements
- adenosine triphosphate
- used to store chemical energy for short periods of time
- energy stored in the bonds connects the 3 phosphate molecules
- when those bonds are broken, a HUGE amount of energy is released
polymer to monomer?
- proteins
- carbs
- nucleic acids
- amino acids
- simple sugars
- nucleotides
Name the 5 classes of membrane protein (ARRET)
- Adhesion proteins
- Recognition proteins
- Receptor proteins
- Enzymatic proteins
- Transport proteins
Name 2 ways cell membranes can be different
- different fluidity
- different composition of proteins and phospholipids
Name 4 non-membranous cell components (EXCEPTIONS- RCCC)
*trevor’s question
- ribosomes
- cytoskeleton
- centrisomes
- centrioles
name the function of adhesion proteins + give 1 example
- attach a cell to either another cell or a solid surface outside of the cell
- ex: integrins are adhesion proteins bindinf to the extracellular matrix
name the 3 functions of recognition proteins + give 1 example
- identify the cell as being from the species (or even the individual organism) that it is from
- helps other important cells recognize it as ‘’ being like them’’ (acts as a ame tag for cells)
- often have a carb attached to them, called a glycoprotein
- ex: MHC proteins
name 2 steroid functions
- Hormones; for communication between cells → ETC- etsrogen, testosterone, cortisone
- Components of cell membranes → cholesterol for membrane fluidity
5 properties of water
1) water can interact with many molecules in many different ways
2)water molecules stick to polar molecules
3) water-based solutions can be acidic, basic or neutral
4) the temperature of water is relatively difficult to change
5)water forms a unique solid
the size and polarity of water make it a good solvent because:
*key word: dissolve
-dissolve ionic bonds
-dissolve molecules with polar covalent bonds
-dissolve small, non-polar gases
-important because many substances can be dissolved in a cell’s cytoplasm to participate in chemical recations required for life
what are hydrophobic interactions (technically not a chemical bond)
-when large non polar molecules stick together in an aqueous environment
- that is due to the hydrogen-bonding ability of water
explain why each property of water is important
1) important to allow cells to create barriers in different aqueous compartments
2) important to allow terrestrial plants to move water from roots to leaves (CAPILLARY ACTION)
3) important because different biochemical reactions in the cells requires different pH conditions
4)important in order for living things to moderate their body temperature
5)important because
1- prevents bodies of water from freezing totally solid
2-allows for marine life in winter and polar areas
explain the importance of carbon in biological molecules
the carbon atom makes up the skeleton because of its VERSATILITY
- can bond w up to 4 atoms
- can form single double or triple bonds
- carbon skeletons can have many different shapes
what are functional groups + explain their importance in biological molecules
Functional groups are: groups of atoms attached to the carbon skeleton that give every biological molecule its unique properties.
→ less stable, and will react much more readily than the carbon skeleton.
→Determines the behaviour of the biological molecule.
→Most biological molecules use the same general set of functional groups.
name the basic characteristic of all lipids (2)
→The many carbon and hydrogen atoms make non-polar covalent bonds with each other.
→Lipids are very hydrophobic because of their size and all the non-polar bonds.
name the three major classes of lipids in nature
1) Triglycerides
2) Phospholipids
2) Steroids
name 4 common carbs in nature and their function
1) glucose
2) sucrose
3) cellulose
4) glycogen
functions:
of glucose+ fructose
- short term energy storage
-building blocks to make polysaccharides
fct of cellulose:
main structural component of plants + used for protection, unbranched, parallel, every 2nd glucose inverted
fct of glycogen:
polysaccaheride, energy reservoir/storage in animals, branched structure for enzymes to capture energy easily from the ends of the branches
How can nucleotides act as signaling molecules (3)
→ The single nucleotide cyclic AMP (cAMP) acts as a signaling molecule.
→ It acts as a chemical signal within one cell, not from one cell to a different cell. An intracellular messenger.
→Often called a second-messenger, because it is often the second signaling molecule to respond after a membrane receptor binds its specific signaling molecule.
why can we say that a fatty acid chain has dual properties? + give an example
- because there is a hyphophilic head and a hydrophobic tail in the fatty acid chain
- ex: soap
→ head washes away oils/ dirt (hydrophilic) and tail picks up oil/dirt (hydrophobic)
how does systemic signaling work in plants
through transport of signaling molecules through vascular tissues
what is the primary role of albumin in eggs
serving as a reservoir of amino acids for the growing embryo to utilize
what is the primary role of secondary messenger signaling molecules
Initiating signal transduction cascades within the cytoplasm
what structural feature distinguishes phospholipids from triglycerides
Presence of phosphate group
(they both have fatty acids, watch out 4 confusion)
what is the function of receptor-mediated endocytosis in cells
Receiving SPECIFIC molecules from the extracellular environment
define pynocytosis
The bulk uptake of extracellular fluid and solutes by membrane invagination
which type of transport involves the movement of molecules or ions across the cell membrane through protein channels
facilitated diffusion
which type of chemical bonding involves the sharing of electrons between atoms
covalent bonding (STRONG bond)
which specialized ell-cell junction is responsible for cytoplasmic connection between adjacent plant cells
plasmodesmata
explain why water molecules can form hydrogen bonds with each other
made of O atoms (partial negative charge) and made of H atoms (partial + charge), which are required for a H bond to occur
