Organic Molecules(Macromolecules)

Pages 42-55

MacromoleculesOrganic molecules; they all contain carbon

Carbohydrates (Polysaccharides)Lipids (fats)ProteinsNucleic Acids (DNA/RNA/ATP-ADP)

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CARBOHYDRATESCarbohydrates

Contain carbon, hydrogen, and oxygenBuilding blocks of carbohydrates:

Monosaccharides—simple sugars (glucose, galactose)

Disaccharides—two simple sugars (lactose, sucrose)

Polysaccharides—long chains of linked simple sugars (starch, glycogen)

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LIPIDSLipids

Contain carbon, hydrogen, and oxygen Carbon and hydrogen outnumber oxygen

Most abundant in the body include: Triglycerides: stored energy Phospholipids: components of cell membranes Steroids: structural components of:

Hormones (adrenal gland) vitamin D synthesis cell membranes

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PROTEINSComprise about 50% of the body’s dry weightHydrogen bonds are an essential part of

protein structureAllow intramollecular bonding of the same protein

Multiple functions including:A role in cell functionActing as enzymes, hormones, and antibodiesBuilding blocks are amino acids

We can sufficiently synthesize 10 of the 20 The rest of the a.a. need to be consumed in diet-

“essential amino acids”

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NUCLEIC ACIDS- DNA and RNADNA/RNA: The cell’s genetic material

DNA resides w/in the nucleus and stays there Hydrogen bonds secure both strands of DNA

mRNA/tRNA are created through protein synthesis

NUCLEIC ACIDS – ATP/ADPATP/ADP: The cell’s energy currency

Hydrolysis reaction breaks bonds in phosphates to release energy ATP becomes ADP (adenosine diphosphate)

ADP is “re-energized” using consumed food and O2 Cellular respiration

ATP is stored and used depending upon availability of glucose and oxygenThree metabolic pathways use/produce it

Figure 2.23a Three examples of how ATP drives cellular work.

(a) Chemical work. ATP provides the energy needed to drive energy-absorbing chemical reactions.

ATPPi

PiP

A BB

AADP

Figure 2.23b Three examples of how ATP drives cellular work.

Pi

Solute

ADPATP

P PiMembraneprotein

(b) Transport work. ATP drives the transport of certain solutes (amino acids, for example) across cell membranes.

Figure 2.23c Three examples of how ATP drives cellular work.

ATPPi

ADP

Relaxed smoothmuscle cell

Contracted smoothmuscle cell

(c) Mechanical work. ATP activates contractile proteins in muscle cells so that the cells can shorten and perform mechanical work.