LIPIDS OILS FATS AND WAXES 2 basic forms
LIPIDS – OILS, FATS AND WAXES • 2 basic forms: Saturated and unsaturated • What does your family use to cook with? • Unsaturated is better: olive oil, vegetable oil • Saturated can cause health problems: butter, steak fat, cheese
TYPES OF FATS SATURATED FATS UNSATURATED FATS • Only single bonds between carbons because each carbon holds maximum number of hydrogens • Have at least 1 double bond between carbons • Solid at room temperature • Considered to be a healthier fat • Associated with health risks: high cholesterol • Usually liquid at room temperature
LIPIDS: FUNCTIONS • Lipids are a stored form of energy (long-term energy). This will not be used until the carbohydrates run out.
LIPIDS: FUNCTIONS • Lipids are an important component of cell membranes. • Lipids help insulate the body
PROTEINS
CHARACTERISTICS OF PROTEINS • Contain carbon, hydrogen, oxygen, nitrogen, and sulfur • Basic building block is the amino acid – Amino acids make them up • Shape helps determine function • Examples: Fish, poultry, eggs
FUNCTIONS OF PROTEINS • Serve as structural components of animals – help build muscle! • Serve as control molecules (enzymes) – What are enzymes? Proteins that speed up chemical reactions. • Serve as transport and messenger molecules • Help fight infection - antibodies
AMINO ACID • There are 20 different amino acids! • Made up of amino group and carboxyl group – same for ALL amino acids • Have “R” group – different for all amino acids
SOME AMINO ACIDS
LEVELS OF ORGANIZATION – Proteins have four levels of structure. 1. A protein’s primary structure is the sequence of its amino acids. 2. Secondary structure is the folding or coiling of the polypeptide chain. 3. Tertiary is the 3 D structure 4. Quaternary (4 th level) describes how the chains are arranged
HOW DO PROTEINS LOSE THEIR SHAPE? • Proteins can denature – bonds break so they do not function correctly • p. H and temperature can cause this • Could be BAD if enzyme is needed for important body functions (we will talk more later!)
NUCLEIC ACIDS
DO HOTDOGS HAVE DNA? After watching the video, discuss the following with your partner. How can hotdogs have DNA? What does it mean to discover a new species of cockroach?
NUCLEIC ACIDS – Nucleic acids are macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus. – Nucleic acids are polymers assembled from individual monomers known as nucleotides.
DNA STRUCTURE • • DNA is made of nucleotides • Nitrogenous base • Deoxyribose sugar • Phosphate These are put together in long chains to make up a DNA molecule
NITROGENOUS BASES • 5 types of nitrogenous bases –Adenine (A) –Thymine (T) –Cyotsine (C) –Guanine (G) –Uracil (U) • Nitrogenous Bases pair: –A-T (DNA) –A-U (RNA) –C-G (DNA/RNA)
TWO EXAMPLES • DNA – Deoxyribonucleic Acid • RNA – Ribonucleic Acid • They are made of very similar things (nucleotides), but there are many differences! – One similarity: RNA and DNA have nitrogenous bases, sugars, and phosphates – One difference: RNA is single-stranded (single helix) and DNA is double-stranded (double helix)
NUCLEIC ACIDS - FUNCTION • Store genetic information • Transmit heredity • Blueprint (hold the plans) for proteins
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