Bio 02 test

Know the definitions, examples, concepts, identify the structures where applicable and characteristics of the following terms:

- Saturated(characteristics, examples, how it behaves at low temp):

Def- have a maximum number of hydrogen atoms

Ex- stearic acid

-zig zag molecule

-fats are made from saturated fatty acids

-solid at room temp

-animal fats are saturated

-unsaturated fats (characteristics, examples, how it behaves at low temp):

Def- have one or more double bonds

Ex-Oleic Acid

-cis-double bond causes bending

-fats are made from unsaturated fats or oils

-liquid at room temp

-plant fats and fish fats are usually unsaturated

More on Fats:

• hydrogenation is the process of converting unsaturated to saturated fats by adding hydrogen (trans fats)

• Fats main function is energy storage

• Humans and mammons store fat in adipose cell (cushion withal organs)

- Levels of structure of a protein (primary, secondary, tertiary, quaternary) with the bonds, terms, examples

• prolines account for more than 50% of the dry mass of most cells

• Functions include: structural support, storage, transport, cellular communications, movement, and defense against foreign substances

• - polypeptides are made up of same set 20 amino acids (a protein is made up of one or more polypeptides )

•

Primary- protein in its unique sequence of amino acids

• like the orders of letters in a long word (structure is determined by inherited genetic information)

Secondary- found in most proteins, coils and folds in a polypeptide chain)

• result in hydrogen bonds between repeating constituents of polypeptide backbone

• Helix or pleated sheet

Tertiary-determined by interactions among various side chains (R groups)

• interactions include hydrogen bonds, ionic bonds, hydrophobic, and van der waals

• Strong covalent bonds called disulfide bridges may reinforce the proteins structure

Quaternary- what a protein consists of multiple polypeptide chains

• result when two or more polypeptide chains from on macromolecule

• Ex) collagen (three polypeptides coiled like a rope), hemoglobin (two alpha chains and two beta chains)

Proteins and their functions:

Enzymatic protein-Selective acceleration of chemical reactions (digestive enzymes)

Structural Protein-Support (keratin in hair, horns, feathers)

Storage protein-storage of amino acids (protein in milk, storage proteins in plant seeds)

Transport protein-transport of other substances (hemoglobin, transport proteins) and allow the passage of hydrophilic substances across the membrane, selectively permeable

Hormonal proteins-coordination of organisms activities (insulin)

Receptor proteins-response of cell to chemical stimuli (receptors in never cell membranes)

Contractile proteins- movement (proteins in cilia and flagella)

Defense proteins- protect against diseases (Antibodies)

Functional protein- one or more polypeptide twisted, folded, and coiled (ribbon or Dots)

- Monosaccharide(examples)- carbohydrates or single sugar, Molecular formula and multiples of CH20 or C6H1206 (glucose), and are classified by the carboxyl group (as aldose or ketone) the number of carbons in the carbon skeleton

• feed cells

-disaccharides(examples)-is formed when a dehydration reaction joins two monosaccharides called glycosidic linkages (glucose+galactose= lactose intolerant)

-polysaccharides(examples)-polymers of sugar have storage and structural roles

• structure and function is determined by sugar monomers and position of glycosidic linkages

• The polysaccharide is a major structural component of the cell plant walls

-triacylglycerol (examples)-three fatty acids are joined to glycerol by an ester linkage

- Lipids(composition, function, characteristics- polar, non-polar, bonds)-do not form polymers, no affinity for water, hydrophobic because they consist of mostly hydrocarbons which form non-polar covalent bonds, mains are fats phospholipids, and steroids

• fats are glycerol and fatty acids

• Fatty acid is a carboxyl group with a long carbon skeleton

-proteins(composition, function, characteristics- polar, non-polar, bonds)-polymer to monomer, made of polypeptide bond (20 amino combined with one polypeptide (sugar)

-carbohydrates(composition, function, characteristics- polar, non-polar, bonds)-monomer, includes sugars and polymers of sugars, polysaccharide (polymers composed of many sugar building blocks), mono to poly (sugars form rings)

-nucleic acids (composition, function, characteristics- polar, non-polar, bonds)-monomer, DNA and RNA polymers to monomers, hydrolysis

- Amino acids:

distinctive parts-a carboxyl and amino acids and bonded by polypeptide bonds and contains Asymmetric carbon also called alpha carbon

must be able to label

bonds between amino acids- called polypeptide bonds

R group classes- amino properties differ due to side chains which are R groups

• amino acids are linked by peptide bonds

• Polypeptide is a polymer of amino acids

• The have an H on one end and an OH on another (H—OH or OH-H)

• Side chains are outside the main polymer group

- Denaturation-a loss of proteins native structure (proteins to unravel)

• ex) alterations in pH, salt concentration, temp., causes this

-renaturation- protein returns to its native structure

- Purpose of DNA, RNA and protein-DNA stores genetic information, RNA acts as an intermediary in protein synthesis by carrying instructions from DNA, and proteins carry out the diverse functions necessary for life

- Nucleotides and their nitrogenous base matches (A-T,C-G,A-U)

• made of 5 carbon sugar, phosphate

• nucleaic acids are polymers called polynucleotides

• Each polynucleotide is made of monomers called nucleotides

- DNA structure and characteristics:amino acid sequence of a polypeptide is programmed by a unit of inheritance called gene

• dna is a nuclear acid

• Provides directions for its own replication

• DNA directs messenger rna

• Forms double helix

backbone-the sugar-phosphate backbone, a structural framework of nucleic acids (DNA and RNA) composed of alternating sugar and phosphate group

H-bonds- found in tertiary structure weakest bond of them all, and interactions between R-groups

covalent bonds- nonmetal and nonmetal and also called a glycosidic linkage

Difference between RNA and DNA- (ribose and Deoxyribose)

RNA- single stranded, composed of A,T,G,C

DNA- double stranded or single, composed of A,G,C,U

- Central Dogma – molecular biology describes the flow of genetic information in cells: DNA-RNA-Protein

- Characteristics and functions of:

-nucleus- to store the cell's genetic material, DNA, act as the control center for all cellular activities, directing the cell's functions like growth, protein synthesis, and reproduction; it is considered the information processing center of the center

• nuclear envelope- consists of a lipid bilayer

• Pores regulate entry and exit of molecules

• Protein holds shape (nuclear lamina)

• Nucleolus- controls ribosome assembly

-ribosome- Translates the genetic code carried by messenger RNA (mRNA) into a chain of amino acids, which then fold to form functional proteins; essentially acting as the "protein factory" of the cell. (double membrane have proteins made by free ribosomes, contain DNA)

-mitochondria-sites for cellular respiration, generates ATP (double membrane have proteins made by free ribosomes, contain DNA), semi-liquid system, proteins are made in the matrix

◦ Outer membrane

◦ Inner membrane space

◦ Inner membrane

◦ Matrix

-cytoskeleton- a network of fibers extending through cytoplasm, organizes cells structures and activities (help maintain and support cells shape)

◦ Microtubules (shapes cells, guides organelles, separates chromosomes and control beating of cilia and flagella), microfilaments (intermediate filaments)

-cilia- help move cells around, move fluids past cells, and move particles away from cells.

-flagell- helps to propel a cell through the liquid. Some special flagella are used in few organisms as sensory organs that can sense changes in pH and temperature.

-Golgi body-flattened sacs called cisternea, modifies products of the ER, manufactures certain macromolecules, sorts and packages materials into transport vesicles

-lysosome- membranous sac of hydrolytic enzymes that can digest macromolecules, hydrolysis proteins, fats, polysaccharides, and nucleic acids

Hydrolysis- polymers are disassembled into monomers

Condensation reaction- many monomers bond together through a loss of water

-vesicles- small, membrane-bound sacs within cells that play a crucial role in transporting materials, storing substances, and facilitating various cellular processes

-chloroplasts- found in plants and algae, sites of photosynthesis (called plastids, green pigmented chlorophyll), contains: lobes, plastids

• structure is

◦ Outer membrane

◦ Inner membrane space

◦ Inner membrane

◦ Stroma

◦ Thylakoid membrane

◦ Thylakoid space

-vacuole- food vacuole (formed by phagocytosis), Contractile vacuoles (pump excess water out), central vacuoles (hold organic compounds and water)

-endomembrane system

◦ contain:

◦ Nuclear envelope

◦ Endoplasmic reticulum

‣ Smooth ER- lack ribosomes, synthesizes lipids, metabolizes carbohydrates, detoxifies poison, stores calcium

‣ Rough ER- ribosomes studding its surface (bound ribosomes which release glycoproteins, distributes transport vesicles(protein surrounded membranes)

◦ Golgi apparatus

◦ Lysosomes

◦ Vacuoles

◦ Plasma membrane

• components are either continuous of connected via transfer by vesicles

- Light microscopy VS. electron microscopy

Light- visible light passes through a specimen and the through glass lenses

Electron- beam of electrons to magnify and examine specimens at the atomic scale

- Prokaryotes VS eukaryotes

Eukaryotic- internal membranes that divide cell into organelles (Plant, animal, fungi, Protista), DNA is in membrane, linear DNA wraps around protein to fit, MRNA goes outside nucleus to see ribosomes bond,

Prokaryotes- cell wall, DNA is floating, circular DNA, bonded by phospholiester, bacteria and archae

- Be able to label a figure of an animal cell

- Cytoskeleton –types and proteins that they are made of

• Made up of motor proteins, microtubules, microfilaments, and intermediate filaments

- Plasmodesmata- channels that perforate plant cell walls (water and small solutes can pass from cell to cell)

-tight junctions- membranes of neighboring cells are pressed together, preventing leakage of extracellular fluid

-gap junctions- provide cytoplasmic channels between adjacent cells

-desmosomes- fasten cells together into strong sheets

- Membrane fluidity

• Decreasing fluidity with decreasing temperatures

• Increased unsaturated hydrocarbons changes this

- Osmosis-the diffusion of water across a selectively permeable membrane

-passive transport- a substance that diffuses across a biological membrane (requires no energy to make it happen)

-active transport- uses energy to move solutes against their gradient

◦ Facilitated diffusion is passive

◦ Some transport proteins can move against their solutes against their concentrated gradients

-diffusion- the tendency for molecules to spread out evenly into the available space, molecules can move separately or together

- Cell membrane – structure, function, cholesterol

• phospholipid bilayer with embedded proteins and and cholesterol(cholesterol in protein looks like octagons in the lipid bilayer) and regulates what enters and exits the cell while maintaining its shape

• Cholesterol maintains fluidity, (increases temp, aren’t soluble thus increases solid state) decreased temperature (prevents solidification

- Fluid Mosiac model-movement of phospholipid, kinks in the fatty acid chains

• a membrane is a fluid structure with a “mosaic” of various protiens embedded into it

• Phospholipids in the plasma membrane can move within the bilayer

• Lipids drift laterally and rarely across the membrane

Proteins in cell membranes –

integral- embedded

peripheral- surface attached

transmembrane- spanning the membrane

- Properties of phospholipid parts: two fatty acids and a phosphate group are attached to glycerol

• two fatty acids are hydrophobic

• Phosphate group and its attachments form a hydrophilic head

• When added to water they make a bilayer (tail pointing inside)

• Major component of cell membrane

- Water's passage through cell membrane- aquaporins

- Membrane potential – voltage across membrane

- Movement of potassium across cells (requires energy)- The movement of potassium ions across cell membranes against their concentration gradient (from low to high) requires energy and is achieved through active transport, specifically the sodium-potassium pump

- Exocytosis- transport vesicles migrate to the membrane, fuse with it, and release their contents

-pinocytosis- he ingestion of liquid into a cell by the budding of small vesicles from the cell membrane

- Facilitated diffusion- transport proteins speed the passive movement of molecules across the plasma membrane (passive transport)

- Hypertonic— effect on cell/solution- cell loses water (shrivels)

-hypotonic— effect on cell/solution- cell gains water (explodes)

-isotonic – effect on cell/solution- no water movement across the gradient)

- Sodium-potassium pump- is the major electrogenic pump of animal cells