Biochemistry Anatomy Unit 2

Inorganic compounds

Lack carbon w/H & O

High heat capacity

Prevents sudden changes in temperature

High heat of vaporization

Useful cooling

Polar solvent properties

• dissolves and dissociates ionic substances

• Body’s major transport medium

Salts

• inorganic

• Ionic compounds that dissociate in water

• Ions (electrolytes) conduct electrical currents in solutions

Acids

Can release detectable hydrogen ions in solution

Bases

Proton acceptors such as OH- and ammonia

Acidic pH

0-6.99

Alkaline pH

7.01-q4

Buffers

Mixture of compounds that resist pH changes

Important organic compounds

Contain carbon, hydrogen, and oxygen

Organic compounds

Many are polymers- chains of similar units (monomers or building blocks)

Carbohydrates

Contains carbon, hydrogen, and oxygen in a 1:2:1 ratio

Monosaccharide

Simple sugar

Glucose

Disaccharide

Two simple sugars jointed by dehydration synthesis

Polysaccharide

Long branching chains of linked simple sugars

Starch, cellulose, glycogen

Lipids

Contain carbon, hydrogen, and oxygen not in a 1:2:1 ratio

Triglycerides

• composed of 3 fatty acids & 1 glycerol

• Source of stored energy

• Found in subcutaneous tissue and around organs

Saturated fatty acid

Single bonds between C atoms ; maximum number of H

Solid

Unsaturated fatty acids

• One or more double bonds between C atoms

• Oils

Phospholipids

Chief component of cell membranes

Proteins

• Contains C,H,O, and Nitrogen

• Made of amino acids

Fibrous

• Extended and strandlike proteins

• Keratin, collagen

Globular

• Compact spherical proteins

• Examples: antibodies, hormones, enzymes

Enzymes ( Functional proteins)

• acts as biological catalysts

• Increase the rate of chemical reactions

Nucleic acids

• composed of carbon, oxygen, hydrogen, nitrogen, and phosphorus

• Their structural unit, the nucleotide, is composed of N-containing base, a pentose sugar, and a phosphate group

Two major classes

DNA & RNA

DNA

Deoxyribonucleic acid

ATP

• Adenine- containing RNA nucleotide with two additional phosphate groups

• Chemical energy used by all cells

• Energy is released by breaking high energy phosphate bond

• ATP is replenished by oxidation

Nucleus

• Control center of the cell

• Contains genetic material

Chromatin

Scattered form of DNA throughout the nucleus in thread form

Chromosomes

Chromatin condenses to form chromosomes when the cell divides

Cytoplasm

Material outside the nucleus and inside the plasma membrane

Mitochondria

• carry out reactions where oxygen is used to break down food

• Provides ATP for cellular energy

Ribosomes

Sites of protein synthesis

Rough ER

• studded with ribosomes

• Produces protein

smooth ER

produces lipids

Golgi apparatus

Modifies and packages proteins

Lysosomes

conatins enzymes that digest non-usable materials within the cell

Peroxisomes

Membranous sacs of oxidase and catalase

enzymes to protect cell from metabolic waste

Cytoskeleton

provides the cell with an internal framework

Centrioles

direct formation of mitotic spindle during cell division in animal cells

Cellular Projections

Not found in all cells

Used for movement

Plasma membrane

• barrier for cell contents

• Hydrophilic heads

• Hydrophobic tails

Membrane proteins

inserted into the membrane

Function: transport proteins, enzymes, or receptors

Peripheral proteins

Loosely attached to integral proteins on outside of

Function: Enzymes, motor proteins, cell-to-cell links, provide

support on intracellular surface membrane

Transport

a protein that spans the membrane may provide a hydrophilic channel across the membrane.

Receptors for signal transduction

A membrane protein exposed to the outside of the cell may have a binding site with a specific shape that fits the shape of a chemical messenger

Attachment to cytoskeleton and extracellular

matrix

Elements of the cytoskeleton (cell’s internal supports) and the extracellular matrix (fibers and other substances outside the cell) may be anchored to membrane proteins, which help maintain cell shape and fix the location of certain membrane proteins.

Enzymatic activity

A protein built into the membrane may be an enzyme with its active site exposed to substances in the adjacent solution.

Intercellular joining

guide cell migration and other cell-to-cell interactions.

Cell-cell recognition

identification tags that are specifically recognized by other cells.

Microvilli

Finger-like projections that increase surface area for absorption

Tight Junctions

Prevent fluids and most molecules from moving between cells

Desmosomes

“Rivets” or “spot-welds” that anchor cells together

Gap Junctions

Transmembrane proteins form pores that allow small molecules to pass from cell to cell

• For spread of ions between cardiac or smooth muscle cells

Passive transport

No energy is required

Active transport

The cell must provide metabolic energy