Biology chapter 5 and 6

Protein

Function: building blocks of life, defense transport, cellular communication, structural support

Monomer: amino acids

Polymer: polypeptides 

Examples: enzymes, signaling, proteins, and receptor proteins

Lipids

Function: long term energy storage

Monomer: fatty acids and glycerol

Polymer: no true polymer

Examples: oil, phospholipid bilayer, and steroids

Nucleic acid

Function: storage and transport of genetic info

Monomer: nucleotides

Polymer: polynucleotides

Examples: DNA and RNA

Carbohydrate

Function: short term energy storage and building material

Monomer: monosaccaride

Polymer: polysaccharides

Examples: cellulose (beta linkages), starch and glycogen (alpha linkages)

carbohydrates are connected through glycosidic linkages, which form through dehydration synthesis

Structural isomers have the same molecular formula but different positions of bonds between atoms.

True

Non polar molecules are hydrophilic, while polar molecules are hydrophobic.

False

Carboxyl groups act as acids, while amino groups act as bases.

True

Dehydration reactions remove a water molecules to form a bond, while hydrolysis adds a water molecule to break a bond.

True (lysis=cut, cutting bond with H2O)

Lipids and important components:

\-hydrophobic, made mostly of hydrocarbon regions

\-does not include true polymers

-function for long-term energy storage

-ester linkages formed through dehydration reactions

-fats, phospholipids, and steroids

Saturated fatty acids

\-"saturated with hydrogens" (max number of hydrogens)

-no double bonds

-solid at room temperature

-mostly animal fats

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Phospholipids

\-two fatty acids and a phosphate group attached to glycerol -fatty acid tails are hydrophobic, while phosphate heads are hydrophilic

-this allows for a formation of bilayers, as the phospholipids will self assemble in water to orient themselves to have their tails face the interior

Steroids and example of them:

\-lipid characterized by a carbon skeleton with four fused rings

-ex. cholesterol; component of animal cell membranes and a precursor to other steroids

Monosaccarides

\-simple sugar, monomer of carbohydrate, usually multiples of CH2O

Disaccharides

\-two monosaccarides linked together

Polysaccharides

\-multiple monosaccharides bonded together

-polymer, complex carbohydrates/complex sugars

Cellulose

\-structural polysaccharide in plants-give plans cell walls rigidity

-contains beta linkages

Starch

\-storage polysaccharide in plants

-contains alpha linkages

Glycogen

\-storage polysaccharides in animals

\-stored in liver and muscle cells

Enzymes

\-enzymes break down and digest carbs

-enzymes that digest starch can hydrolyze alpha linkages, but NOT the beta linkages in cellulose, so cellulose passes through as insoluble fiber in animals

-some microbes use enzymes to digest cellulose, such as those found in symbolic relationships in herbivores

What bond is formed in the formation of polysaccharides?

Glycosidic linkages

\*One OH is removed and one H is removed causing dehydration/removal of the water causing the O that is still standing to go over to the middle of the glycosidic linkage \*Glucose; most common monomer

Identify and describe some examples of proteins

\-Enzymes: accelerate chemical reactions, helps break down carbohydrates and foods

-Transport proteins: transport substances, ex: hemoglobin transports oxygen 

-Receptor proteins: response of cell to chemical stimuli, ex: nerve cells

Hormonal proteins: coordinate organism activities, ex: insulin regulating blood sugar

Contractile and motor proteins: ex: cilia and flagella, actin and myosin cause muscle contractions

Storage: ex: ovalbumin in egg white providing amino acids for developing embryo

Draw and label the structure of an amino acid. Which part determines its properties? Why are amino acids so important?

R group: determines its properties. Amino acids are so important because the order of amino acids determines a protein of 3D structure, which then determines protein function.

Amino acids are joined together by peptide bonds (why we cal the polymer of amino acids polypeptide)

Explain the levels of protein structure

Primary: amino acid sequence, determined by genetic information (DNA sequence)-

Secondary: coils and folds, called alpha helixes and beta pleated sheets, result of hydrogen bonds between common components of the backbone (NOT R GROUPS)

Tertiary: interactions among side chains (R groups), include hydrogen bonds, ionic bond, hydrophobic interactions, and Van Der Waals interactions (weak), ex: disulfide bridges between Cysteines \\n Quaternary: multiple polypeptide chains

How can a proton become denatured?

\-Temperature

-Sal concentration: hypertonic/hypotonic solution

-pH

What are our "units of inheritance"? What are they mad of?

\-Genes are our units of inheritance

-Consists of DNA, a nucleus acid made of nucleotides

What are the monomers of nucleic acids?

\-Nucleotides

-Composed of a nitrogenous

\* a nucleotide is only the nitrogenous base and sugar

What are the two major examples of nucleic acids/ How do they differ?

DNA:

\-double stranded

-codes for mRNA

-ATCG

-deoxyribose sugar which is missing at 2' OH

-antiparallel and complementary strands run in opposite directions (5' to 3')

RNA

-single stranded (but complementary pairing may still occur within a strand or between two strands)

-different functions, mRNA, tRNA, rRNA

\-AUCG

-ribose sugar which contains a 2' OH

Purines

\-six membered ring fused to a five-membered ring (2 rings)

\-A and G

\-AG, big about the rings, HUGE school

Pyrimidines

\-single six-membered ring

\-T,C,U (3 bases)

Which of the following links together the monomers of nucleic acid?

phosphodiester linkage

Which of the following is NOT a significant function of proteins?

Energy storage

Which of the following is true of unsaturated fatty acids?

They contain double bonds

Which of the following is the most common monosaccharide?

Glucose

In DNA, there are two hydrogen bonds between A and T nucleotides, and three hydrogen bonds between C and G

True

Side chains (R groups) are involved in the secondary structure of protein folding

False; involved in the Tertiary

Starch is a storage carbohydrates

True

Saturated fatty acids are solid at room temperature because they contain double bonds

False; they do not contain double bonds

A nucleotide contains of a nitrogenous base, a peons sugar, and a phosphate group

False, nucleotides lack a phosphate

What organisms are found in prokaryotic cells?

\-bacteria

\-archaea

What organisms are found in eukaryotic cells?

\-protists

\-fungi

\-animals

\-plants

What are the basic features of all cells? Define their function/role:

Plasma membrane; indicates cell from environment but allows specific substances to be exchanged

Cytosol

matrix for everything to float inside

Chromosomes

carry genes-genetic information

Ribosomes

translate information from mRNA to make proteins

Prokaryotic cells:

\-no nucleus

\-DNA in unbound nucleic region

\-no membrane-bound organelles

\-cytoplasm bound by plasma

\-ribosomes

Eukaryotic cells:

\-DNA contained in a nucleus

\-cytoplasm contained in region between plasma membrane and nucleus

\-contains membrane-bound organelles

Describe the plasma membrane. Why is it so important?

\-selective barrier that allows passage of oxygen, nutrients, waste

\-made of phospholipids (hydrophilic heads face out) (hydrophobic tails face in)

\-necessary for metabolism-resources in and waste out

Describe the function and components of the nucleus:

\-Nucleus: contains most of the cell’s DNA

\-Nuclear envelop contains the double membrane and is surrounded with pores lined with pore complexes that regulate entry and exit of molecules

\-DNA is organized into chromosomes containing condensed chromatin = DNA + histone proteins

nucleus: sit of rRNA synthesis within nucleus

Explain the function and list the components of the endomembrane system

Function: regulates protein traffic and performs metabolic functions

Components:

\-nuclear membrane

\-endoplasmic reticulum

\-golgi apparatus

\-lysosomes

\-vacuoles

\-plasma membrane

Endoplasmic reticulum:

\*Biosynthetic factory, continuous with nuclear envelope

Smooth ER

Rough ER

Smooth ER

\*lacks ribosomes

\-synthesizes lipids

\-detoxifies drugs and poisons -adds OH

\-stores calcium ions

Rough ER

\*studded with ribosomes

\-bound ribosomes secrete glycoproteins, (protein+sugars)

\-distributes transport vesicles

\-is a membrane factory for the cell

Golgi Apparatus

\*Shipping & receiving center

\-consists of cistern: flattened membranous sace

\-modifies products of ER

\-sorts and packages materials into vesicles

Lysosomes

\*Digestive compartments

\-membranous sac of hydrolytic enzymes that work best in acidic environment

\-phagocytosis forms food vacuoles that fuse with lysosomes to digest contents

\-autophagy: recycling cell’s own organelles and macromolecule

Vacuoles

\*Diverse maintenance compartments

\-food vacuoles

\-contractile vacuoles; found in freshwater protests, pump excess water out of cells

\-central vacuoles-plant cells, contain sap, serve as plant cells main respiratory of inorganic ions (K+/CL-)

Mitochondria and Chloroplasts

\*Change energy from one form to another

Mitochondria:

\-cellular resiration

use oxygen to generate ATP

\-foldings called cristae

\-intermembrane space and mitochondrial matrix

Chloroplasts:

\-plants and algae

\-sites of photosynthesis

\-contain chlorophyll and enzymes

\-thylakoids stocked to form granum

\-stomainternal fluid

Ribosomes

\*rRNA and protein build protein

\-free ribosomes-in the cytosol

\-bound ribosomes- on the outside of the R or nuclear envelope

Peroxisomes

\*Oxidation

\-enzymes remove hydration atoms and transfer them to oxygen to form hydrogen peroxide

\-reaction functions:

\-using oxygen to break fatty acids for fuel for respiration

\-in liver, they detoxify alcohol and other compounds

What is the cytoskeleton? What is its role?

\-network of protein filaments that support the cell and maintain its shape

\-interacts with morrow proteins to produce motility

\-provides the ‘tracks’ for vesicles and organelles to walk on using motor protein feet

What three fibers make up the cytoskeleton? What are they made of and what are their roles?

Microtubules:

\-tubulin dimers

\-chromosome movement in cell division

\-movement of organelles

\-shaping the cell

\-cellular reconstruction, separate chromosomes and cell division

\-animal cells-grow out a centrosome near the nucleus

\-centrosome has a pair of centrioles-each with a triplets of microtubules in a ring

Microfilaments

\-actin subunits in twisted double chain

\-muscle contraction

\-myosin

\*actin is powered by ATP to assemble its filamentous form; serves as a track for the movement of a motor protein called myosin

Intermediate filaments

\-keratins

\-anchorage of nucleus

Cell wall

\-extracellular structure that distinguishes plant from animal cells

\-prokaryotes, fungi, protists also have cell walls

\-protects plant cell, maintains shape, prevents excessive water uptake

\-made of cellulose fibers embedded in other polysaccharides and proteins’-may have multiple layers

Tell me about the extracellular matrix:

\-in animal cells

\-made of glycoproteins: collagen, proteoglycans, and fibronectin

\-regulate cell behavior by communicating with a cell through integrins

Which structure is directly responsible for the formation of proteins within the cell

ribosomes

Which of the following is NOT true of Eukaryotic cells

DNA is located in a nucleic region

cell membrane

cholesterol is very important in cell membrane because it functions to keep the fluidity of the membrane

Hydroxyl

\-polar covalent (react with water) or other polar molecules

Carboxyl

\-acts as an acid

\-can increase {H+"} I solution

\-importat element of amino acids

Carbonyl

\-looks like an eel

\-double bond between C and O

\-found in ketones and aldehydes

Phosphate

\-high electronegativity of oxygens gives negative charge-can react wit H2O

\-polar

\-found in ATP

Methyl

\-regulates gene expression by transcription

\-affects shape and function of sex hormones

\-nonpolar

Sulfhydryl

\-fond in amino acid cysteine

\-involved in formation of secondary structures of protein

Amino

\-acts as a base

\-can lower {H+} by trapping it in solution

\-important element element in amino acids

Denaturation

\-breaking of many weak linkages or bonds

\*hydrogen bonds

\-the process of denaturation occurs with proteins, in which these molecules are being deactivated

\*affecting shape of structure which will overall affect the function

Bonds

Lipids: ester linkages

Carbohydrates; glycosidic linkage

Amino Acids: peptide bonds

Nucelic acid: phosphodiester