Molecules+GS

Grant Sanders Human Biology Period 1

2.3 Molecules of Life (p.27) SUBMIT TO YOUR WIKI PAGE (INNER FISH UNIT) Define...organic molecules- Type of molecule that contains carbon, hydrogen, and often oxygen as well.

1. What are the four classes of molecules unique to cells? The four classes are carbohydrates, lipids, proteins, and nucleic acids.

2. What type of recation occurs during the synthesis of macromolecules? When macromolecules are constructed dehydration reactions occur.

2.4 Carbohydrates (p. 28-29) Define... Monosaccharide- Simple sugar; a carbohydrate that cannot be decomposed by hydrolysis.

Disaccharide- Sugar that contains two units of a monosaccharide.

Glucose- Six- carbon sugar that organisms degrade as a source of energy during cellular respiration.

Polysaccharide- Polymer made from sugar monomers; the polysaccharides starch and glycogen are polymers of glucose monomers.

Starch- Storage polysaccharide found in plants that is composed of glucose molecules joined in a linear fashion with few side chains.

Glycogen- Storage polysaccharide that is composed of glucose molecules joined in a linear fashion but have numerous branches.

Cellulose- Polysaccharide that is the major complex carbohydrate in plant cell walls.

1. What is the usual function of carbohydrates in humans? Carbohydrates supply humans with quick short- term energy.

2. What is the difference between a simple carbohydrate and the various complex carbohydrates? A simple carbohydrate gives organisms short burst of energy, and complex carbohydrates contain many glucose units, so these give off longer bursts of energy.

3. Of what benefit is fiber in our diet? The benefit is that fiber stimulates movements of the large intestine, which prevents constipation.

2.5 Lipids 1. Define saturated fats, unstaturated fat, and trans fat. Saturated fats- Fatty- acid molecule lacking double bonds between the atoms of its carbon chain. Unsaturated fats- Fatty- acid molecule that has one or more double bonds between the atoms of its carbon chain.

Trans fat- Fats, which occur naturally in meat and dairy products of ruminants, that are also industrially created through partial hydrogenation of plant oils and animal fats.

2. What is the main function of fats and oils and what are they composed of? Fats and Oils main function is to store energy, and they are composed of one glycerol molecule and three fatty acid molecules.

3. What are the uses of phospholids and steroids in the body? Phospholipids are the primary component of cellular membranes, and steroids are used to form testosterone in males and estrogen in females.

2.6 Proteins (p. 32-34) Define peptide bond, and denaturation Peptide bond- The type of covalent bond that joins two amino acids. Denaturation- The loss of normal shape by an enzyme so that it no longer functions.

1. What are the major functions of proteins in an organism? The major functions of proteins in an organism are support, enzymes, transport, defense, hormones, and motion.

2. How does an amino acid get its name? NH2 which is an amino group, and COOH which is an acid group

3. How does the shape of a proein relate to its function. Once a protein loses its normal shape, it is no longer able to perform its usual function.