Lecture Review on Lipids and Proteins

This set of flashcards covers key vocabulary and concepts related to lipids, proteins, tissues, and their functions within the human body.

Glyceride

A glycerol molecule with one or more fatty acids attached, important as an energy source and for insulation and protection in the body.

Lipids

-mainly hydrophobic, such as fats, oils, and waxes

-made mostly of carbon and hydrogen atoms

-inluce: fatty acids, elcosanoids, glycerides, steroids, phospholipids, and glycolipids

fatty acids

-long chains of carbon and hydrogen with a carboxyl group at one end

-relatively non polar, except the carboxyl group

-fatty acids may be: saturated with hydrogen, unsaturated(one or more double bonds in tall), monounsaturated, polyunsaturated.

Elcosanoids

-cannot be synthesized, so it must be obtained from the diet

-it derived from a fatty acid called arachidonic acid

Leukotrienes

active in immune system

prostaglandins

-short-chain fatty acid

-local hormones

Monoglyceride

fatty acids attached to a glycerol molecule .

Diglyceride

glycerol plus two fatty acids

Triglyceride

Glycerol plus three fatty acids, also called triacylglycerols or neutral fat, has three important functions(energy source, insulation, protection)

steroids

-four-ringed carbon structures with an assortment of functional groups

what is an example of a steroid

cholesterol

cholesterol

-component of plasma(cell) membranes

• sex hormones such as estrogen and testosterone

• steroid hormones such as corticosteroids

• steroid derivatives called bile salts

phospholipids and glycolipids

-Both can be made by our cells

-contains a diglyceride attached to either a phosphate group(phospholipid) or a sugar(glycolipid)

-structural lipids-these are components of plasma membranes

proteins

-are the most abundant and important organic molecules

-contains basic elements(carbon, hydrogen, oxygen, and nitrogen)

-20 amino acids are monomers that combine to form proteins(polymers)

what are the seven major protein functions

support(structural proteins), movement(contractile proteins), transport(transport (carries) proteins)), buffering(regulation of pH), metabolic regulation(enzymes), coordination and control(hormones), defense(antibodies)

protein structure

-long chains of amino acids

-each amino acid consists of

1. central carbon atom

2. hydrogen aton

3. Amino group

4. carboxyl group

5. variable side chair, or R grouwhath

what are dehydration synthesis between

-the amino group of one amino acid and the carboxyl group of another amino acid,

• forms a peptide bond

primary structure

the sequence of amino acids along a polypeptide. it is the sequence of a chain of amino acids

secondary structure

Hydrogen bonds form spirals or pleats. The hydrogen bonding of the peptide backbone causes the amino acids to fold into a repeating pattern

tertiary structure

coiling and folding produce three-dimensional shape. this is a three dimensional folding pattern of a protein due to side chain interactions

Quaternary structure

Final protection complex produced by interactive polypeptide chains. This is a protein consisting of more than one amino acid chain

globular proteins

• soluble spheres with active functions

• shape is based on tertiary structure

fibrous proteins

-sturcutural sheets or strands

-shape is based on secondary or quaternary structures

Proteins part 2

• Enzymes are catalysts

-not changed or used up in the reaction

substates

they bind to an active site on an enzyme

what do enzymes exhibit

1. Specificity: catalyze only one type of reaction

2. Saturation limits: enzymes become saturated

3. Regulation:by other cellular chemicals

cofactor

an ion or molecules that binds to an enzyme before substrates can bind

coenzymes

nonprotein organic cofactors(vitamins)

Amino acids

The building blocks of proteins, there are 20 different amino acids that link together to form proteins.

Denaturation

change in shape and loss of function due to heat or pH

glycoproteins

• large proteins+small carbohydrates

• includes enzymes, antibodies, hormones, and components of plasma membrane

• mucus production

proteoglycans

• large polysaccharides+polypeptides

• increases viscosity of fluids

Nucleic acids

-large organice molecules found in the nucleus

-store and processes information

Deoxyribonucleic acid(DNA)

• determines inherited characteristics

• directs protein synthesis

• controls enzyme production

• controls metabolism

Ribonucleic acid(RNA)

controls intermediate steps in protein synthesis

structure or nucleic acids

-DNA and RNA consists of long chains of nucleotides(monomers), which contains

1. a pentose sugar(deoxyribose or ribose)

2. Phosphate group

3. Nitrogenous Base(A,G,T,C,or U)

DNA and RNA

-DNA consists of a pair of nucleotide chains

• called complementary stands

• hydrogen bonds between opposing nitrogenous bases holds the strands togehter

-RNA consists of a single chain of nucleotides

• Messenger RNA(mRNA)

• transfer RNA(tRNA)

• Ribosomal RNA(rRNA)

High-energy compounds

most high-energy compounds are derived from nucleotides

phosphorylation

-the process of adding a phosphate group to another molecule

-produces a high-energy bond

Adenosine Monophosphate (AMP)

Nucleotide that contains one phosphate group

Adenosine Diphosphate(ADP)

contains two phosphate groups

ATP (Adenosine triphosphate)

A high-energy compound containing three phosphate groups

Adenosine Triphosphatase(ATPase)

enzyme that catalyzes the conversion of ATP to ADP

Tissue

group of cells similar in structure that performs common or relation functions

what are the 4 basic tissue types

epithelial, connective, muscle, and nervous.

nervous tissues

internal communication(brain, spinal cord, and nerves)

muscle tissues

-contracts to cause movement

• muscles are attached to bones(skeletal)

• Muscles of heart(cardiac)

• Muscles of walls of hollow organs(smooth)

epithelial tissues

forms of boundaries between different environment, products, secretes, absorbs,filters

• skin surface(epidermis)

• lining of GI tract organs and other hollow organs

Connective tissues

-supports, protects, binds other tissues together(bones, tendons, fat and other soft padding tissues)

what are the two main types if epithelial tissues?

1. covering and lining epithelial(on external and internal surfaces)

2. Glandular epithelia(secretory tissue in glands)

characteristics of epithelial tissue

1. cells have polarity-apical(upper, free) and basal(lower, attached) surfaces that differ in structure and function

2. Apical surfaces may bear microvilli or cilia

3. The noncellular basal laminate of lygoprotein and collagen lies adjacent to the basal surface

4. are composed of closely packed cells(continuous sheets held together by tight junctions and desmosomes)

5. Bound to the basal laminate and reticular and reticular laminate(basement membrane);basal laminate is a noncellular adhesive sheet or glycoproteins secreted by the epithelia. Acts as a filter and scaffolding for migration of cells

functions of epithelium

• protection(keeps stuff out)

• permeability(controls what can get across.into cell),

• sensation(studded with nerve endings

• Produce secretions(gland cells synthesis and secrete products

maintaining the integrity of epithelia

1. intercellular connections

2. Attachment to the basement membrane

3. Epithelia maintenance and and repair

membrane junctions

specialized attachment sites important for securing cells together and providing communication pathways

three type of membrane junctions

1. tight junction:prevents fluids and most molecules from moving between cells, adhesion belt attaches to terminal web

2. Desmosome:rivets or “spot welds” that anchor cells together, 2 kinds:spot desmosomes and hemidesmosomes

3. Gap Junction: transmembrane proteins(connexions) form pores that allow small molecules to pass from cell to cell, for the spread of ions between cardiac or smooth muscle cells

how to classify the epithelia

there are two questions you can ask: How many layers?(1=simple epithelium, more layers are stratified epithelium) and what shape is the cell?(squamous, cuboidal, and columnar

overview of epithelial tissues

For each of the following 8 types of epithelia, you would note the description, function, and location

Simple Squamous Epithelium

Description: single layer of flattened cells with disc-shaped central nuclei and space cytoplasm; the simplest of the epithelia

function: Allows passage of materials by diffusion and filtration in sites where protection is required is not important; secretes lubricating substances in serosae

location: kidney glomeruli; air sac of lungs; lining of heart, blood vessels, and lymphatic vessels; lining of ventral body cavity

Epithelia: simple squamous

-Two specialized locations

• Endothelium(the lining of lymphatic vessels, blood vessels, and the heart

• Mesothelium(the epithelium of serous membranes in the ventral body cavity)

Stratified squamous Epithelium

Description: Thick membrane composed of several cell layers; basal cells are cuboidal or columnar and metabolically active; surface cells are flattened(squamous); in the keratinized type, the surface cells are full of keratin and dead; basal cells are active in mitosis and produce the cells of the more superficial layers

-function: protects underlying tissues in areas subjected to abrasion

-location: nonkeratinized type forms the moist lining of the esophagus, mouth, and vagina; keratinized variety forms the epidermis of the skin, a dry membrane

simple cuboidal epithelium

Description: single layer of tubelike cells with large, spherical central nuclei

Function: secretion and absorption

Location: kidney tubules. ducts and secretory portions of small glands; ovary surface

simple columnar epithelium

Description: Single layer of tall cells with round to oval nuclei; some cells bear cilia, layer may contain mucus secreting unicellular glands(goblet cells)

Functions:Absorption: secretion of mucus, enzymes, and other substances; ciliated type propels mucus or reproductive cells) by ciliary action

Location: Conciliated type lines most of the digestive tract(stomach to anal canal), gallbladder, and excretory ducts of some glands; ciliated variety lines small bronchi, uterine tubes, and some region of the uterus

Pseudostatified columnar epithelium

Description: single layer of cells differing heights, some not reaching the free surface; nuclei seen at different levels; may contain mucus secreting cells and bear cells

functions: secretion particularly of mucus, propulsion of mucus by ciliary action

location nonciliated type in male’s sperm-carrying ducts and duts of large glands; ciliated variety lines the trachea, most of the upper respiratory tract

epithelia:stratified cuboidal

• quite rare in body

• found in some sweat and mammary glands

• typically two cell layers thick

Epithelia:stratified columnar

• limited distribution in body

• small accounts in pharynx, make urethra, and lining some glandular ducts

• also occurs at transition areas between two other types of epithelia

transitional epithelium

description:resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar; surface cells dome shaped or squamous life, depending on degree of organ stretch

function: stretches readily and permits distention of urinary organ by contained urine

location:lines the ureters, urinary bladder, and part of the urethra