Chemistry of life

Moving Cellular Materials

Energy for life

Nature of Matter◦ Atoms◦ Elements◦ Compounds and Molecules◦ Molecular compounds◦ Ionic compoundsMixturesOrganic compounds

CarbohydratesLipidsProteinsNucleic Acids

Inorganic Compounds◦ Importance of water◦ Characteristics of water

All things in universe contain matter and possess energy

Matter is anything that has mass and takes up space

Energy is anything that brings about change

Matter is made up of atoms◦Atoms are the smallest part of an

element◦There are 92 naturally occurring

elements on earth◦Composed of a nucleus in center where protons and neutrons are found

◦Surrounding the nucleus are electrons◦Protons are positively charged particles◦Electrons are negatively charged

particles◦Neutrons have no charge (neutral)

Electons (-) Protons (+) Neutrons (0)

When matter is made up of only one kind of atoms it is an element (pure substance)

Each element has its own symbol (one or two letter symbol) H, He, O , Na

Organized on periodic table by mass, number of protons, and symbols

Matter is mostly in combinations with other elements (NaCl), H2O

Some matter is composed of same elements O and C make 83% of human body S,P,O,N,C and H make up 99 % of living

matter

Molecular compounds have elements that share their electrons

The elements that share electrons in a molecule take on different chemical properties that the elements themselves◦ H and O share electrons to form H2O, in a

proportion of 2 H to every 1 O, ◦ H2O is different than the elements H or O gas

Atoms are normally neutral Sometimes atoms loose or gain electrons and

become either positive or negative charged Ions are charged atoms (+ or -)

Atoms that combine as result of these charged particles produce ionic compounds

Ionic compounds are important in organism because they send messages, transport O, move things in and out of cell

Sometimes substances combine but don’t change their own identities which are called mixtures (salt water)

Can be solid, liquid or gas or combination of each

Solutions are mixtures that are evenly mixed◦ NaCl andH2O are solutions which retain own

characteristics Suspensions are special solutions that

some of the substances settle out of solution ◦ Blood is an example

Always contain Carbon and Hydrogen and associated with living things

Organic compounds groups are:Carbohydrates: supply energy, made of sugars and starches (C,H,O)

Lipids: don’t mix with water, fats and oils stored release larger amounts of energy (C,H,O,P)

Proteins: made of amino acids that are building blocks of many structures in organism, (C,H,O,N,S)

enzymes are special proteins that regulate all chemical reactions in

cells

Nucleic Acids: molecules that store coded information in cells (C,H,O,N,P)

Directs cells activities and genetic information

DNA and RNA

Most are made from elements other than Carbon

Few atoms in molecules Needed by organisms to carry out life

functions H2O, Calcium Phosphate (CaPO4),

Hydrochloric Acid (HCl) , Sodium bicarbonate (NaCO3)

Life thought to began in water Living organisms are composed of at least

50% water and depends on water to live Water necessary for plants to grow and live Chemical reactions in living things takes

place in water solutions and materials are moved in water solutions in cells

Water atoms are arranged so that there is a negative and positive area on the molecule

These positive and negative poles causes it to act like a magnet to other water molecules

A strong film is formed allowing small insects to walk on water

When heat is added to water, water molecules are so strongly attached to each other the temperature changes slowly and acts like an insulator (constant temperature inside cells)

When water freezes, ice crystal forms, and the spacing between molecules remain constant

Distance between molecules in frozen states is farther apart, ice floats

Water freezes from top down and provides an insulation from extremely cold temperatures allowing organisms to survive in cold water under ice

Passive Transport or Active Transport

Endocytosisi or Exocytosis

Cell membrane acts like a screen to allow certain things in or out of cell

When no energy is required to transport material across the cell membrane it is called passive transport

There are 3 methods materials are moved through the cell : diffusion, osmosis, facilitated diffusion

Movement of molecules from areas of greater concentrations to areas of less concentrations is called diffusion

Smoke moving in a room Movement of molecules continue until

equilibrium is met (evenly distributed) Diffusion of oxygen in blood is moved into

red blood cells in lungs and deposited in your toes.

Diffusion of water across cell membrane is osmosis

Plant cells will become limp if placed in salt water

Animal cells will swell up in presence of water and will burst if too much water enters the cell

Sugar molecules are large and need transport proteins to help them enter cells

Facilitated diffusion is the process of passive transport that allows large molecules to pass through cell membrane

Transport proteins help cells allow large molecules like sugar molecules in

without using energy as it crosses cell membrane

Active transport is the movement of molecules across the cell membrane that requires energy ◦Roots of plants always take in minerals

into cells already high in concentration (this is opposite of diffusion)

◦Requires energy to get them into cells◦Transport protein is required to move

across cell membrane

Process of allowing substances into a cell by surrounding it with the cell is called endocytosis◦Finger stuffed in balloon is an example of

a cell surrounding a substance Vesicles are formed when cell membrane

folds in on itself: they then are moved and stored in cells to be used

Opposite of endocytosis

Large materials are removed from cells

Materials are packaged in vesticles and fuse with cell membrane and are diffused through cell membrane out of cell

Cells in your stomach release chemicals that help digest food

Page 259 reference

http://highered.mcgraw-hill.com/olc/dl/120068/bio02.swf

Trapping and using energy◦Photosynthesis◦Producing carbohydrates◦Storing carbohydrates◦Cellular respiration◦Breaking down carbohydrates◦Fermentation◦Related processes

Metabolism is the total of all the chemical reactions that take place in organisms

Enzymes are needed to allow organisms to utilize food. They help make food usable

Enzymes causes larger molecules to break down into smaller molecules and enzymes are still available to break down other large molecules (page 261)

Producers (plants) produce their own food using the sun and storing the food in form of sugars and carbohydrates

Releases oxygen as a by product

Plants have organelles called chloroplast that carry green pigment called chlorophyll that captures the suns energy and transforms it to food that stores energy in chemical bonds Carbohydrates and sugars are produced by the plants

Oxygen is given off

Plants utilize sun to produce glucose C6H12O6

During photosynthesis, more food is produced than used for energy and it is stored as carbohydrates and starches

Animals eat plants and break down these chemical bonds of carbohydrates and starches to get their energy

During cellular respiration chemical reactions occur that break down food into simpler substances and release their stored energy when the bonds are broken

Opposite of photosynthesis as the product of photosynthesis is the materials used in cellular respiration and visa versa:

Carbon dioxide and water is released

Fermentation is a process when cells do not have enough oxygen for cellular respiration

Glucose is broken down and energy is released in cellular respiration in the mitochondria

When the demand for energy is too great, the cytoplasm sometimes break down glucose

When this happens lactic acid is produced causing burning and soreness in muscles

Bacteria uses fermentation to produce their energy

The lactic acid produced produces yogurt and cheeses

Yeast cells use fermentation that release alcohol and carbon dioxide as wastes in bread making

Producers use photosynthesis to produce food

All living things use respiration or fermentation to release energy stored in food

Photosynthesis and cellular respiration use each of the other products as their source of production

CO2 + H2O C6H12O6 + O2

Light energy

Photosynthesis