Biology I Biochemistry, Atoms, Subatomic Particles, Elements 3.00_Chemistry of Biology Biology I Biochemistry, Atoms, Subatomic Particles, Elements Slides 1-28

The Chemical Context of Life CHEMISTRY FOR BIOLOGY The Chemical Context of Life

Why Are We Studying Chemistry Biology has chemistry at its foundation

What is Biochemistry? Biochemistry = chemistry of life. Biochemists use physical and chemical principles to explain biology at the molecular level. Basic principles of biochemistry are common to all living organism

How Does Biochemistry Impact You? Medicine Agriculture Industrial applications Environmental applications

Principle Areas of Biochemistry Structure and function of biological macromolecules Metabolism – anabolic and catabolic processes. Molecular Genetics – How life is replicated. Regulation of protein synthesis

Chemistry of Life Atoms, Elements, & Compounds Chemical Reactions Water and Solutions The Building Blocks of Life

Chemistry of Life Elements: simplest form of a substance - cannot be broken down any further without changing what it is Atom: the actual basic unit - composed of protons, neutrons, and electrons of atoms = elements

Atom Chemistry is the study of matter. Atoms are the building blocks of matter. Neutrons and protons are located at the center of the atom called the nucleus. Protons are positively charged particles (p+). Neutrons are particles that have no charge (n0). Electrons are negatively charged particles that are located outside the nucleus (e-).

The Basics Everything is made of matter Matter is made of atoms Atoms are made of: protons + mass of 1 nucleus neutrons 0 mass of 1 nucleus electrons - mass <<1 orbits Just like cells are the basic unit of life, the ATOM is the basic unit of matter. They are very small. If placed side by side one million would stretch a distance of 1cm. Different kinds of atoms = elements

Atoms Atoms have 3 components: protons, neutrons, and electrons The type of element (carbon, iron, etc. ) is entirely determined by how many protons are in the nucleus. protons and neutrons are in the nucleus Protons have a +1 charge Neutrons have no charge Electrons circle around the nucleus, in a series of shells. Electrons have a -1 charge Chemical bonds are created by movements of the electrons between atoms The number of protons determines which element the atom is. Hydrogen: 1 proton, carbon = 6 protons, oxygen = 8 protons. Biological and chemical processes never change the number of protons in any atom. Normally, the number of electrons is equal to the number of protons, so the atom has no electrical charge: it is neutral.

Atomic structure determines behavior The number of protons in an atom determines the element # of protons = atomic number this also tells you # of electrons All atoms of an element have same chemical properties all behave the same properties don’t change

3 quarks = 1 proton or 1 neutron Subatomic Particles Quarks component of protons & neutrons 6 types He 3 quarks = 1 proton or 1 neutron

Atoms

Models of Atom

ATOMIC MASS = 4 (PROTONS & NEUTRONS) Electrons Electrons are not present within the nucleus, instead THEY REVOLVE AROUND THE NUCELUS OF THE ATOM & FORM THE ELECTRON CLOUD NEUTRONS PROTONS ATOMIC # = 2 (PROTONS) ATOMIC MASS = 4 (PROTONS & NEUTRONS) - + + ELECTRONS -

Atoms The weight of one proton or neutron. Amu-stands for atomic mass unit. It's a very small unit of mass used to express the mass of atoms and molecules, conceptually equal to 1 gram divided by Avogadro’s constant.  An atomic mass unit is approximately 1/12 the mass of an atom of carbon-12. Atoms https://www.delsearegional.us/Academic/Classes/highschool/science/chemistry/firstyear/Notes/academic/Unit02/slideshows/atomicstructure.html

Electron Cloud In the 1920’s scientists determined that electrons do not orbit the nucleus like planets. Instead, they can be found anywhere in a cloudlike region around the nucleus. (the cloud is a visual model) An electron’s movement is related to its energy level. or specific amount of energy it has. Electrons of different energy levels are likely to be found in different places of the ‘cloud’.

Modern Model The modern model describes an atom as consisting of a nucleus that contains protons and neutrons, surrounded by a cloud-like region of moving electrons. The number of protons always equals the number of electrons. This ensures that the overall atom is neutral. The number of neutrons does not have to equal the number of protons. Neutrons don’t affect the charge of an atom because they have no charge.

Particle Masses Compared It takes almost 2000 electrons to equal the mass of just one proton. A proton and a neutron are about equal in mass. Atoms are too small to describe with everyday units of mass (grams, kilograms). Scientists use units known as Atomic Mass Units (AMU) to describe the mass of atoms and its particles. A proton or neutron has a mass equal to about one amu (atomic mass unit).

Scale & Size of Atoms Most of the volume of an atom is the space in which the electrons move (electron cloud). The nucleus is extremely small compared to the size of the overall atom. In a speck of dust there may be 10 million billion atoms.

Atomic Number Every atom of an element has the same number of protons. Ex/ Every atom of carbon (C) has 6 protons. The number of protons in the nucleus is called the Atomic Number. Atomic number identifies an element.

Elements An element is a pure substance that cannot be broken down into other substances by physical or chemical means. There are 118 known elements, 92 of which occur naturally. Each element has a unique name and symbol. All of this data, and more, are collected in an organized table called the periodic table of elements.

Elements An element is a pure substance that cannot be broken down into other substances by physical or chemical means. There are 118 known elements, 90 of which occur naturally. 25 were synthesized (made) by scientists Each element has a unique name and symbol.

Life requires – 25 chemical elements About 25 elements are essential for life Four elements make up 96% of living matter: carbon (C) • hydrogen (H) oxygen (O) • nitrogen (N) Four elements make up most of remaining 4%: phosphorus (P) • calcium (Ca) sulfur (S) • potassium (K)

Naturally Occurring Elements in Human Body

Elements Song Element Song http://www.privatehand.com/flash/elements.html Element Song https://www.youtube.com/watch?v=zGM-wSKFBpo

Elements Song The NEW Periodic Table Song (Updated) https://www.youtube.com/watch?v=VgVQKCcfwnU