Chapter 2 – Water, Biochemistry, and Cells

Ch. 1 ReviewOne hypothesis states that eating chicken noodle soup is an effective treatment for colds. Which of the following results does this hypothesis predict?

a. people who eat chicken noodle soup have shorter colds than do people who do not eat chicken noodle soupb. people who do not eat chicken noodle soup experience unusually long and severe coldsc. cold viruses cannot live in chicken noodle

soupd. people who eat chicken noodle soup feel

healthier than do people who do not eat chicken noodle soup

Ch 1. Review

There is a strong correlation between obesity and the occurrence of a disease known as type 2 diabetes-that is, obese individuals have a higher instance of diabetes than nonobese individuals do. Does this mean that obesity causes diabetes? Explain.

Chemistry in Biology

Properties of Living OrganismsMaintain Homeostasis (constant internal environment with a changing external environment):• Growth• Movement• Reproduction• Response to external

stimuli• Metabolism

– Breakdown of chemicals to produce energy

– Synthesis of chemicals – Excretion of wastes

Water: Essential to Life

• Components of Water– 2 hydrogen atoms, 1 oxygen

atom– Polar: positive hydrogen side

and negative oxygen side• Allows to dissolve substances

like salt

• Properties of Water– Facilitates chemical reactions– Cohesive– Moderates temperature

https://www.youtube.com/watch?v=aVmU3CLxvgU

Atomic Structure & Chemical Bonding• Atoms have protons (+) & neutrons (o) in their nucleus• Electrons (-) have are located outside the nucleus and

travel in orbitals• Atoms have valence electrons on their outer orbital

Types of Bonds• Covalent: atoms share

electrons• Ionic: attraction of

charged atoms by similar, opposite charges

• Hydrogen: weak bond that forms when a partially positive hydrogen atom is attracted to a partially negative atom

Carbon in Living Organisms

• Organic Chemistry: branch of chemistry that is concerned with complex carbon-containing molecules

• Carbon has the ability to create bonds with up to four other elements

Macromolecules

• Protein• Carbohydrates• Lipids• Nucleic Acids

https://www.youtube.com/watch?v=H8WJ2KENlK0

Structure and Function of Carbohydrates

• Structure:– Chemical composition – carbon, hydrogen, &

oxygen with a 1:2:1 ratio– Monosaccharides (sugar) are the monomer,

disaccharides have 2 monosaccharides, & polysaccharides have more than 1

• Function: – Source of energy (ATP energy is produced)– Structure – cell wall in plants & exoskeleton in

insects

Structure and Function of Protein

• Structure:– Contain an amino group (NH2

+) and carboxyl group (COO-)

– Monomer is an amino acid• Function:– Structure in cytoskeleton in animal cells– Movement in muscle cells– Regulate chemical reactions via enzymes

Structure and Function of Lipids

• Structure:– Contain a glycerol and fatty acid tail (hydrocarbons

made out of a chain of hydrogen and carbon)• Function:– Fats store energy within living organisms– Steroids chemical signaling and aid in membrane

fluidity– Phospholipids are the basic component of the cell

membrane

Structure and Function of Nucleic Acids

• Structure:– Monomer are nucleotides– Nucleotides consist of a sugar, phosphate, and base

• Types of bases include uracil (RNA only), adenine, thymine (DNA only), cytosine, & guanine

• Types of sugars include deoxyribose in DNA and ribose in RNA

• Function:– RNA synthesizes proteins– DNA stores genetic information

Cell Structure & Function

https://www.youtube.com/watch?v=cj8dDTHGJBY

Structure and Function of the Cell Membrane

• Structure:– Made out of a phospholipid bilayer– Contains proteins that aid in transport, structure,

and communication– Fluid Mosaic:

• Function: Regulates what goes in and out of the cell– Semi-permeable: some substances cross and

prevent others from crossing

Cell Organelle Functions

• Protein Production– Nucleus: contains genetic information on how to make a

protein– Ribosome: makes the protein– Rough Endoplasmic Reticulum: location of ribosomes

• Transport– Rough Endoplasmic Reticulum: packs proteins in a vesicle– Golgi Apparatus: sorts, modifies, packs, and ships proteins– Lysosome: breaks down wastes or defective proteins for

recycling or elimination out of the cell– Cell Membrane: regulates what goes in and out of the cell

Cell Organelle Functions

• Energy Production– Mitochondria:

creates ATP energy from glucose

– Chloroplast: converts sun energy into glucose (chemical energy)

Properties of Prokaryotic Cell• No membrane-bound

organelles• No nuclei• Unicellular organisms• Contain ribosomes,

cell membrane, cell wall, & cytoplasm

• Cell walls made of peptidoglycan

Properties of Eukaryotic Cells

• Contain nuclei• Membrane-bound organelles• Contain cell membrane, cell wall, cytoplasm,

ribosomes, Golgi Apparatus, Rough & Smooth Endoplasmic Reticulum, Mitochondria, Chloroplast, & Lysosome