PowerPoint Presentation - Nerve activates contractionqrmhsalvarez.weebly.com/uploads/1/2/7/2/12724614/anatomy...Patty Bostwick-Taylor Florence-Darlington Technical College Modified

Lecture Presentation by

Patty Bostwick-Taylor

Florence-Darlington Technical College

Modified by Janice Alvarez, QRMHS

Chapter 2

Basic Chemistry

© 2015 Pearson Education, Inc.

Energy can change the position, physical composition,

or temperature of matter

What again is matter?

Matter and Energy

Matter and Energy

Matter—anything that occupies space and has mass

Matter may exist as one of three states:

Solid: definite shape and volume

Liquid: definite volume; shape of container

Gaseous: neither a definite shape nor volume

Matter and Energy

Matter may be changed

Physically

Changes do not alter

the basic nature of a

substance

Chemically

Changes alter the

chemical composition

of a substance

Forms of Energy

Chemical energy is

stored in chemical bonds

Electrical energy

results from movement

of charged particles

Mechanical energy is

energy directly involved

in moving matter

Radiant energy travels

in waves (light/heat)

Matter and Energy

Energy—the ability to do work.

Has no mass and does not take up space

Kinetic energy: energy is doing work

Potential energy: energy is inactive; stored

Identify examples of

potential and kinetic

energy in these pictures.

Potential and kinetic energy

Potential energy stored in food is converted

to kinetic energy when we exercise.

Chemical Potential Energy (CPE)

Energy and Human Life ATP (adenosine triphosphate)

traps the chemical energy of

food in its bonds

Work Day Assignment

Read Text p.24-26; take notes. Matter and Energy

Workbook p. 17-18

Done Early? Read ahead: p27-30 WBp18-19


Composition of Matter

Atoms

Building blocks of elements

Atoms of elements differ from one another

Atomic symbol is chemical shorthand for each element

Composition of Matter

96 percent of the body is made from four elements:

Oxygen (O)

Carbon (C)

Hydrogen (H)

Nitrogen (N)

Identifying Elements

Atomic number—equal to the number of protons

that the atom contains

Unique to atoms of a particular element

Indirectly tells the number of electrons in an atom

Atomic mass number—sum of the protons and

neutrons contained in an atom’s nucleus

All Elements are Systematically Arranged on the Periodic Table of Elements

Chemistry of Life

There are 92 naturally occurring elements.

Of those 92 elements, 25 are essential to life!

Elements in Living Things

CHOPKINS CaFe

Chemical Composition of the Human Body by Weight

Trace elements are critical for normal growth, development, and body function

An Element Consists of One Kind of Atom

What makes up an atom?

Protons +Neutrons

Electrons -

Nucleus

Subatomic Particles

Electrons determine an atom’s chemical behavior


(a) Hydrogen (H)

(1p+; 0n0; 1e–)

(b) Helium (He)

(2p+; 2n0; 2e–)

(c) Lithium (Li)

(3p+; 4n0; 3e–)

KEY:

Proton

Neutron

Electron

Electrons determine an atom’s chemical behavior

Electron Shells

An atom is considered stable when their

outer shells are filled to capacity.

Octet Rule

Periodic Table of Elements

How do you calculate the number of neutrons?

Atoms of the same element that differ in the number of neutrons are called isotopes.

protons + neutrons in nucleus = atomic mass

Isotopes are identified by their mass numbers.

C-14

Isotopes and Atomic Weight

Radioactivity

Radioisotope

Heavy isotope of certain atoms

Tends to be unstable

Decomposes to more stable isotope

Radioactivity—process of spontaneous atomic decay


Molecules and Compounds

Molecule—two or more atoms of the same elements

combined chemically

Compound—two or more atoms of different

elements combined chemically to form a molecule

of a compoundALL COMPOUNDS

ARE MOLECULES

BUT NOT ALL MOLECULES

ARE COMPOUNDS!!!


Sodium(silvery metal)

Chlorine(poisonous gas)

Sodium chloride (table salt)

Molecules and Compounds

Properties of a compound differ from those of its atoms.


Chemical Reactions

Chemical reactions occur when atoms combine with

or dissociate from other atoms

Atoms are united by chemical bonds

Atoms dissociate from other atoms when chemical

bonds are broken

Electrons and Bonding

How atoms interact with each other depends on

their valence electrons

Bonding involves only interactions between

electrons in the outer (valence) shell


Electrons and Bonding

Atoms with full valence shells do not form bonds


(a) Chemically inert elements

Outermost energy level

(valence shell) complete

2e

He

2e

Ne

8e

Helium (He) Neon (Ne)


Reactive Elements

Valence shell is incomplete

Atoms will gain, lose, or

share electrons to

complete their outer shell

Atoms reach stable state

Bond formation = stable

valence shell

(b) Chemically reactive elements

Outermost energy level

(valence shell) incomplete

1e

H

Hydrogen (H)

(1p+; 0n0; 1e–)

C

2e4e

Carbon (C)

(6p+; 6n0; 6e–)

O

2e6e

Oxygen (O)

(8p+; 8n0; 8e–)

Na

2e8e

1e

Sodium (Na)

(11p+; 12n0; 11e–)

Valence Electrons Determine Reactivity

Chemical Bonds

3 types of chemical bonds Ionic Bonds – when one or more electrons are

transferred from one atom to the other.

Covalent Bonds – when electrons are shared between atoms.

Hydrogen Bonds – weak electrical attraction between molecules .


Chemical Bonds

Ionic bonds

Electrons are completely

transferred from one atom

to another

Chemical Bonds

Ions: charged atoms

Result from the loss or gain of electrons

Anions - negatively charged ion (gained electron(s))

Cations - positively charged ion (lost electron(s))

Opposite charges attract form ionic bonds

CATION ANION

Covalent Bond – electrons are shared

Water H20

MethaneCH4


Chemical Bonds

Covalent bonds

Atoms become stable through shared electrons

Electrons are shared in pairs

Single covalent bonds share one pair of electrons

Double covalent bonds share two pairs of electrons

Reacting atoms

(b) Formation of a double covalent bond

Resulting molecules

OO

Oxygen atom Oxygen atom

or

Molecule of oxygen gas (O2)

O O


Covalent Bonds

Covalent bonds are either nonpolar or polar

Nonpolar

Electrons are shared equally between the atoms of

the molecule

Electrically neutral as a molecule

Example: carbon dioxide

Carbon dioxide (CO2)

Covalent Bonds

Covalent bonds are either nonpolar or polar

Polar

Electrons are not shared equally between the atoms

of the molecule

Molecule has a positive and negative side, or pole

Example: water


Water (H2O)

δ–

δ+δ+


Hydrogen Bonds

Weak chemical bonds

Hydrogen is attracted to the negative portion of a

polar molecule

Responsible for the surface tension of water

Important for forming intramolecular bonds, as in

protein structure


Chemical Reactions

Chemical Reactions Review:

Reactants and Products

Reactants Product

Reactant Products

Anabolic Chemical Reactions

Synthesis reaction (A B AB)

Atoms or molecules combine

Energy is absorbed in bonds

Anabolic activities in the body

Building polymers

Growth

Repair


(a) Synthesis reactions

Smaller particles are

bonded together to form

larger, more complex

molecules.

Example

Amino acids are joined

together to form a protein

molecule.

Amino acid

molecules

Protein

molecule

Anabolic Chemical Reactions

Dehydration synthesis

Remove water to join two molecules

Take out a hydrogen ion [H+]

Take out a hydroxyl group [OH-]

Monomers unite, and water is released

Repeat to form polymers

Catabolic Chemical Reactions

Decomposition reaction

(AB A B)

Molecule is broken down

Chemical energy is released

Catabolic activities in body

Digestion

Energy release


Decomposition reactions

Bonds are broken in larger

molecules, resulting in

smaller, less complex

molecules.

Example

Glycogen is broken down to

release glucose units.

Glucose molecules

Glycogen


Catabolic Chemical Reactions

Hydrolysis

Polymers (large molecules) are broken into monomers

Water molecules are added to break the bonds


Patterns of Chemical Reactions

Most chemical reactions are reversible

Reversibility is indicated by a double arrow

Biochemistry:Inorganic and Organic Molecules Essential to Life

Biochemistry: Essentials for Life

Inorganic compounds

Lack carbon

Tend to be small, simple molecules

Include water, salts, and some acids and bases

Organic compounds

Contain carbon

All are large, covalently bonded molecules

Include carbohydrates, lipids, proteins, and nucleic

acids

Water is the medium for chemical reactions in your body used to sustain life!

Important Inorganic Compounds

Water

Most abundant inorganic compound in the body

Vital properties

1. High heat capacity

2. Polarity/solvent properties

3. Chemical reactivity

4. Cushioning


Hydrogen Bonds!!

Water’s Vital Properties

1. High heat capacity:

Water absorbs and releases a large amount of heat

before it changes temperature

Prevents sudden changes in body temperature

How Water Moderates Temperature

Water heated = hydrogen bonds break = water absorbs and stores large amounts of heat while warming up only a few degrees.

Water cooled = hydrogen bonds form = release heat = water releases large amount of heat while the water temperature drops only slightly.

Solution – a mixture of two or more substances where the molecules are evenly distributed (homogenous), forming an aqueous solution.

Solute (salt)

Solvent (water)

Water’s Vital Properties:

2. Polarity / Solvent Properties

Water as the Solvent of Life!!

When Salt Dissolves in Water

Water Molecule

Water is considered the “UNIVERSAL SOLVENT”,

dissolving other polar and ionic

compounds

3. Chemical reactivity

Water is an important reactant in chemical reactions

Hydrolysis reactions require water

helps digest food

breaks down biological molecules

Water’s Vital Properties


4. Cushioning

Water serves a protective function

cerebrospinal fluid protects the brain from trauma

amniotic fluid protects a developing fetus


Salts (electrolytes – ions that conduct electrical charge)

Contain cations and anions other than H+ and OH–

Easily dissociates into ions when in water

Vital to many body functions

sodium and potassium ions aide nerve impulses


Acids (Acidic)

Release hydrogen ions (H+) when dissolved in water

Example: HCl H+ Cl–

Are proton donors

hydrogen ions are essentially just protons

Strong acids ionize completely; liberate all protons

Weak acids ionize incompletely


Bases (Alkaline)

Release hydroxyl ions (OH–) when dissolved in water

Are proton acceptors

Example: NaOH Na+ + OH–

Strong bases seek hydrogen ions


Neutralization reaction

Acids and bases react to form water and a salt

Example: NaOH HCl H2O NaCl

Acids, Bases and pH

H2O (H+) + (OH-)

Water (hydrogen ion) + (hydroxide ion)

more (H+) ions

more (OH-) ions

pH – “The Rules”

Measures relative concentration of hydrogen ions

Based on the number of protons in a solution,

expressed in terms of moles per liter

Each successive change on the pH scale

represents a tenfold change in H concentration

pH

pH 7 neutral [H+] = [OH-]

pH below 7 acidic [H+] > [OH-]

pH above 7 basic/alkaline [H+] < [OH-]

Buffers—chemicals that can regulate pH change


pH

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Acidic

solution

Neutral

solution

Basic

solution

OH–

OH–

OH–

OH–OH–

OH–

H+

H+

H+

H+H+

H+

OH–

OH–

OH–

OH–

H+

H+

H+H+

H+

H+OH–

OH–

In

cre

asin

gly b

asic

In

cre

asin

gly a

cid

ic

Ne

utra

l

[H

+]=[O

H–]

Examples

1M Sodium hydroxide (pH 14)

Oven cleaner, lye

(pH 13.5)

Household ammonia

(pH 10.5–11.5)

Household bleach

(pH 9.5)

Egg white (pH 8)

Blood (pH 7.4)

Milk (pH 6.3–6.6)

Black coffee (pH 5)

Wine (pH 2.5–3.5)

Lemon juice, gastric juice

(pH 2)

1M Hydrochloric acid (pH 0)

Assignment

Due Friday: Read Text pg. 26-41; take notes. Chemistry – Atoms, Molecules, Bonds, Reactivity Biochemistry – Water, Salts, pH

Workbook pg. 19-22

Done Early? Read ahead: Ch 2 (all) and Workbook up to p.27


Chemical Reactions

Many biological

molecules are

polymers, such as

carbohydrates and

proteins

Polymer: chainlike

molecule made of

many similar or

repeating units

(monomers)

Carbon Compounds:Biological MoleculesChemistry of Carbon - Organic chemistry is the study of all compounds that contain bonds between carbon atoms.

The most versatile element!

Carbon Compounds

Carbon can form single, double or triple bonds with other elements. Each line represents 1 covalent bond (2 electrons).

methane

acetylene benzene

“Giant Molecules”

Macromolecules, or “giant molecules” are formed from monomers, small units that are joined together to form polymers, by a process called polymerization.

There are 4 groups of macromolecules

1.Carbohydrates2.Lipids3.Proteins4.Nucleic Acids


Important Organic Compounds

Carbohydrates

Contain carbon, hydrogen, and oxygen

Include sugars and starches

Classified according to size

Monosaccharides—simple sugars

Disaccharides—two simple sugars joined by

dehydration synthesis

Polysaccharides—long-branching chains of linked

simple sugars

Carbohydrates

Monosaccharides—simple sugars

Single chain or single-ring structures

Contain 3 to 7 carbon atoms

Examples: glucose (blood sugar), fructose,

galactose, ribose, deoxyribose

Carbohydrates

Monosaccharides are single sugar molecules

Carbohydrates

Disaccharides—two simple sugars joined by

dehydration synthesis

Examples include sucrose, lactose, and maltose

Carbohydrates

Starch – polymer of glucose monomers!

CarbohydratesPolysaccharides are large molecules made with monosaccharides


Lipids

Most abundant are

Triglycerides

Phospholipids

Steroids

Contain C, H, O

C and H outnumber O

Insoluble in water, but soluble in other lipids

Lipids

Made mostly from carbon and hydrogen – C, H

Used to…

store energy

form biological membranes

as waterproof covering

as chemical messengers

Lipids

Common lipids in the human body

Neutral fats (triglycerides)

Found in fat deposits

Source of stored energy

Has three fatty acids and one glycerol molecule

Saturated fatty acids

Unsaturated fatty acids

Lipids – triglyceride structure

Lipids (fats) - saturated

Lipids (fats) - unsaturated

Lipids – Good and Bad Fats in Your Diet

Trans fats

Oils solidified by the addition of hydrogen atoms at

double bond sites

Increase risk of heart disease

Lipids – Good and Bad Fats in Your Diet

Omega-3 fatty acids

Found in cold-water fish and plant sources,

flax, pumpkin, and chia seeds; walnuts and soy foods

Appears to decrease risk of heart disease


Lipids

Common lipids in the human body (continued)

Phospholipids

Contain two fatty acids rather than three

Phosphorus-containing “head” carries an electrical

charge and is polar

Charged region interacts with water and ions while the

fatty acid chains (“tails”) do not

Form cell membranes

Phospholipids

Structural component of cell membrane

Lipids

Common lipids in the human body (continued)

Steroids

Formed of four interlocking rings

cholesterol, bile salts, vitamin D, and some hormones

Some cholesterol is ingested from animal products.

The liver also makes cholesterol

Cholesterol is the basis for all steroids made in the body


Steroids

Hormones: chemical messengers

Nucleic Acids

Nucleic acids store and transmit hereditary, or genetic, information.

ribonucleic acid (RNA)

deoxyribonucleic acid (DNA)

Nucleic Acids

Nucleotides are made out of H, O, N, C and P and they contain three parts:

a 5-carbon sugar

a phosphate group

a nitrogenous base

Monomer of nucleic acid

Nucleic Acids

Monomers of nucleotides joined together to form

nucleic acid.



Nucleic acids

Make up genes

Composed of carbon, oxygen, hydrogen, nitrogen,

and phosphorus atoms

Largest biological molecules in the body


Nucleic Acids

Built from nucleotides containing three parts:

1. A nitrogenous base

A Adenine

G Guanine

C Cytosine

T Thymine

U Uracil

2. Pentose (five-carbon) sugar

3. A phosphate group


Nucleic Acids

Deoxyribonucleic acid (DNA)

The genetic material found within the cell’s nucleus

Provides instructions for every protein in the body

Organized by complimentary bases to form a double-

stranded helix

Contains the sugar deoxyribose and the bases

adenine, thymine, cytosine, and guanine

Replicates before cell division


Nucleic Acids

Ribonucleic acid (RNA)

Carries out DNA’s instructions for protein synthesis

Created from a template of DNA

Organized by complementary bases to form a single-

stranded helix

Contains the sugar ribose and the bases adenine,

uracil, cytosine, and guanine

Three varieties are messenger, transfer, and

ribosomal RNA


Nucleic Acids

Adenosine triphosphate (ATP)

Composed of a nucleotide built from ribose sugar,

adenine base, and three phosphate groups

Chemical energy used by all cells

Energy is released by breaking high-energy

phosphate bond

ATP is replenished by oxidation of food fuels


Figure 2.22 ATP—structure and hydrolysis.

(a) Adenosine triphosphate (ATP)

Adenine

(b) Hydrolysis of ATP

Highenergybonds

Phosphates

Ribose

ATP

P P P

P P P

H2O

P P

Adenosine diphosphate

(ADP)

Pi Energy


Nucleic Acids

ADP (adenosine

diphosphate)

accumulates as ATP

is used for energy

Three examples of

how ATP drives

cellular work are

shown next

(a) Chemical work. ATP provides the energy

needed to drive energy-absorbing chemical

reactions.

ATP

Pi

Solute

Pi

PiP

A B

ADP

ADPATP

ATP

Pi

ADP

P PiMembrane

protein

Relaxed smooth

muscle cell

Contracted smooth

muscle cell

(b) Transport work. ATP drives the transport

of certain solutes (amino acids, for example)

across cell membranes.

(c) Mechanical work. ATP activates contractile

proteins in muscle cells so that the cells can

shorten and perform mechanical work.

Proteins

Function

Build bones and muscles

Control the rate of reactions – enzymes

Transport substances into or out of cells

Help fight disease - antibodies

Proteins

Contain N, C, H, O and S

Monomers of amino acids form proteins

There are 20 different amino acids that occur

in nature!!

Proteins – chains of amino acids

Protein Shape

Up to 4 Levels of Organization

1. Sequence2. Amino acids in the chain are

twisted or folded3. Chain is twisted or folded4. Complex proteins with multiple

chains – each chain has a specific arrangement.

Protein shape is very important!!!!



Proteins

Account for over half of the body’s organic matter

Provide for construction materials for body tissues

Play a vital role in cell function

Act as enzymes, hormones, and antibodies

Contain carbon, oxygen, hydrogen, nitrogen, and

sometimes sulfur

Built from amino acids

Proteins

Amino acid structure

Contain an amine group (NH2)

Contain an acid group (COOH)

Vary only by R groups



Figure 2.17 Amino acid structures.

(b) Glycine is

the simplest

amino acid.

(a) Generalized

structure of

all amino

acids.

(c) Aspartic acid

(an acidic

amino acid)

has an acid

group (—COOH)

in the R group.

(d) Lysine (a

basic amino

acid) has an

amine group

(—NH2) in the

R group.

(e) Cysteine (a

basic amino

acid) has a

sulfhydryl

(—SH) group in

the R group,

which suggests

that this amino

acid is likely to

participate in

intramolecular

bonding.

Amine

group

Acid

group


Proteins

Protein structure

Polypeptides contain fewer than 50 amino acids

Large proteins may have 50 to thousands of amino

acids

Sequence of amino acids produces a variety of

proteins


Proteins

Structural levels of proteins

Primary structure

Secondary structure

Alpha helix

Beta-pleated sheet

Tertiary structure

Quaternary structure


Figure 2.18a The four levels of protein structure.

(a) Primary structure. A protein’s

primary structure is the unique

sequence of amino acids in the

polypeptide chain.

Amino

acids

CysGlu Leu Ala Ala

AlaAla

Met Lys Arg His Gly Leu Aps


Figure 2.18b The four levels of protein structure.

(b) Secondary structure. Two types of secondary structure are the

alpha-helix and beta-pleated sheet. Secondary structure is reinforced

by hydrogen bonds, represented by dashed lines in the figure.

Hydrogen bonds

Alpha-

helix

𝛃-pleated sheet


Figure 2.18c The four levels of protein structure.

(c) Tertiary structure. The overall three-

dimensional shape of the polypeptide

or protein is called tertiary structure. It is

reinforced by chemical bonds between

the R-groups of amino acids in different

regions of the polypeptide chain.

Polypeptide

(single subunit)


Figure 2.18d The four levels of protein structure.

(d) Quaternary structure. Some proteins

consist of two or more polypeptide chains.

For example, four polypeptides construct

hemoglobin, the blood protein. Such

proteins have quaternary structure.

Complete protein,

with four polypeptide

subunits


Proteins

Fibrous (structural) proteins

Appear in body structures

Exhibit secondary, tertiary, or even quaternary

structure

Bind structures together and exist in body tissues

Stable proteins

Examples include collagen and keratin


Figure 2.19a General structure of (a) a fibrous protein and (b) a globular protein.

(a) Triple helix of collagen

(a fibrous or structural

protein).


Proteins

Globular (functional) proteins

Function as antibodies, hormones, or enzymes

Exhibit at least tertiary structure

Can be denatured and no longer perform

physiological roles

Active sites “fit” and interact chemically with other

molecules


Figure 2.19b General structure of (a) a fibrous protein and (b) a globular protein.

Heme group

(b) Hemoglobin molecule composed of

the protein globin and attached heme

groups. (Globin is a globular or

functional protein.)

Globin

protein


Enzymes

Act as biological catalysts

Increase the rate of chemical reactions

Bind to substrates at an active site to catalyze

reactions

Recognize enzymes by their –ase suffix

Hydrolase

Oxidase


The enzyme

releases the product

of the reaction.

Figure 2.20 A simplified view of enzyme action.

Substrates (S)

e.g., amino acids

3

The E-S complex

undergoes internal

rearrangements that

form the product.

2Substrates bind at active

site, temporarily forming an

enzyme-substrate complex.

1

Product (P)

e.g., dipeptide

Peptide

bond

Water is

released.

H2O

Energy is

absorbed;

bond is

formed.

Active site

Enzyme (E) Enzyme (E)

Enzyme-substrate

complex (E-S)

Assignment

Due Wed: Read Text p. 42-55; take notes.Organic Compounds

Carbs, Lipids, Nucleic Acids, Proteins, ATP

Workbook p. 23-27

Complete Biological Molecules packet, with partner(s)

Done Early? Read ahead: Ch 3


Documents

PowerPoint Presentation - Nerve activates contractionqrmhsalvarez.weebly.com/uploads/1/2/7/2/12724614/anatomy...Patty Bostwick-Taylor Florence-Darlington Technical College Modified