IB SEHS Topic 3 (FULL)

nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

briefly explain the process of metabolism

all biochemical processes that occur with any living organism to maintain life

Function of carbohydrates

Act as metabolic fuels and energy stores - especially during intense and prolonged periods of exercise

What is the origin of saturated fats?

Animal sources: meat, poultry, full-fat dairy, tropical oils (palm and coconut)

One way dietary guidelines for athletes vary from non-athletes

Athletes require more fluids and energy from macronutrients

Ratio of elements in a carbohydrate

C = 1, H = 2, O = 1

Examples of minerals or trace elements needed by the human body

Ca, Cl, Mg, Na, K, P, Cu, Cr, Fe, I, F, Zn, Se, Mn, Mb

State the chemical composition of a glucose molecule

Carbon, hydrogen, and oxygen (C6H12O6)

State the approximate energy content per 100 g of carbohydrate, lipid, and protein

Carbs: 1760 kJ Lipids: 4000 kJ Protein:1720 kJ

Describe the current recommendations for a healthy balanced diet

Carbs: 50% of diet Fiber: 25-30 grams (6-8 soluble) Water: 64 oz daily Protein: depends on age, gender, and daily activity, anywhere from 80-100 g Fats: 20-30% of our total calorie intake Salt: less than 2,300 mg a day

Explain how glucose molecules can combine to form disaccharides

Condensation reactions remove a water molecule to combine the glucose molecules

State the chemical composition of a protein molecule

Consists of carbon, hydrogen, oxygen, and nitrogen

how does adenosine lose and gain a phosphate molecule

Energy from catabolism attaches a phosphate to ADP forming ATP. Loss of a phosphate from ATP occurs when phosphorylation breaks the bond which provides energy for cellular work.

Function of proteins

Energy source, (1) structural (muscles, bones, skin, cells) types, (2) transport/communication types (neurotransmitters, etc.), (3) protective types (antibodies, mucus), and (4) enzymatic types (digestion, gas transport)

Distinguish between an essential and a non-essential amino acid

Essential: can't be synthesized from the human body, must be obtained from diet non-essential: can be synthesized by the human body

List the macronutrients

Fat(lipid), carbohydrate, protein, and water

Needed to prevent colorectal cancer

Fiber

what occurs in lipolysis

Glucagon and adrenaline are secreted which acts opposite of insulin (lipids are split into fatty acids...)

what occurs in glycogenolysis

Glucagon is secreted by alpha cells from the pancreas and acts opposite of insulin. Adrenaline is also stimulated and reacts like glucagon. Both cause glycogen to be split into glucose molecules.

contribution of the three energy systems during exercise

all three work together but one is always dominant (depended on intensity and duration of exercise)

briefly explain the process of anabolism

building up of simpler molecules into larger molecules, requires an input of energy

Needed for bone density and teeth

calcium (Ca)

An excess amount of this in the diet could cause onset of diabetes

carbohydrates

briefly explain the processes of aerobic catabolism and anaerobic catabolism

catabolism = breaking down complex organic compounds into simpler ones - energy releasing {aerobic = with oxygen, anaerobic = without oxygen}

lysosomes

cell organelle filled with enzymes needed to break down certain materials in the cell

cell respiration

controlled release of energy in the form of ATP from organic compounds

how does ATP-CP resynthesize ATP

creatine phosphate (CP), is broken down to provide a phosphate molecule for re-synthesis of ATP that has been utilized during the initial stages of exercise

first energy source used when muscles contract

creatine phosphate stores

which energy system is mainly used by sprinters

creatine phosphate system (anaerobic) is mainly used, unless the sprint takes longer than 20 seconds

which energy system is mainly used by team sport athletes

depends on the stop/start action and sprints needed for the game; both anaerobic CP and the lactic acid system are used

oxygen deficit

difference between the amount of oxygen consumed during exercise and the amount which would have been consumed if aerobic respiration occurred immediately

oxygen debt

excessive post exercise oxygen consumption (EPOC), demand for oxygen is greater than supply and higher than that of typical resting state

aerobic system (fatty acids)

fats are broken down by beta oxidation that liberates a greater number of electrons, thus more ATP (oxygen required); protein can also be utilized

aerobic fatty acid beta oxidation system

fatty acid => acetyl CoA => Krebs => etc, 1 fatty acid = 14 ATP, slower acting, occurs in mitochondria, carbon dioxide/water are by-products

anaerobic respiration

forms 2 ATP, less energy and no oxygen

aerobic respiration

forms 38 ATP, more energy and requires oxygen

antagonist of insulin hormone

glucagon

energy source used secondly when muscles exercise

glucose

molecule that serves as the major source of readily available fuel for neurons and blood cells

glucose

aerobic glucose oxidation system

glucose => pyruvate => Krebs => etc., 1 glucose = 36 ATP, slower acting, carbon dioxide/water are by products

how do fasting and exercise affect the body's glucose levels

glucose is removed from the blood which stimulates release of glucagon and adrenaline (causing glycogen, lipids and proteins to break down)

glucose forms glycogen

glycogenesis

what process forms glycogen

glycogenesis causes many glucose molecules to link together to form glycogen

what process converts glycogen into glucose

glycogenolysis breaks glycogen into glucose

breakdown of glucose into ATP

glycolysis

anaerobic lactic acid system

glycolysis uses glucose (1 glucose = 2 ATP), occurs quickly, begins when PCr fades (good for hard exercise); lactic acid and lower pH are by products

process that forms glucose from fats or proteins

glyconeogenesis

ETC (electron transport chain)

hydrogen splits into hydrogen ions and electrons, this produces 34 ATP

cristae of mitrochondria

infoldings of the inner membrane of a mitochondria that houses the electron transport chain and the enzyme catalyzing the synthesis of ATP

hormone that directs cells to absorb materials such as glucose or amino acids

insulin

Needed for hemoglobin function

iron (Fe)

what happens to blood glucose levels during exercise

muscle contraction and insulin both stimulate glucose to be taken into muscle cells from the blood (it decreases in the blood but increases in the muscle cells)

Storage location of glycogen

muscles (skeletal) and the liver

Needed for cell membrane production

phospholipids (fats)

mitochondria

powerhouse of the cell, organelle that is the site of ATP production

Which energy source is the least desirable type to be used as fuel?

proteins (muscle)

what happens to pyruvate if oxygen is present

pyruvate enters the mitochondria and is metabolized into carbon dioxide and water

what happens to pyruvate if oxygen is lacking

pyruvate is converted into lactate, transported back to the liver to reform glucose

ribosomes

sites of protein synthesis in cells

Golgi apparatus

stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum

what is glycogen and where is it generally stored

storage molecule of carbohydrates, stored in skeletal muscles and liver

what is glycolysis

the breakdown of glucose by enzymes, releasing energy (ATP) and pyruvic acid

where does glycolysis take place

the cytosol of cells

ATP-CP or creatine phosphate (PCr) system benefit

used for first 10 seconds (with the 2 seconds worth of ATP in the muscle), runs out quickly, ATP quickly regenerated but runs out fast

inner matrix of the mitochondria

viscous cytoplasm containing the mitochondria DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide co-factors, and inorganic ions

lactic acid system (anaerobic glycolysis) is used

when PC is depleted the lactic acid system takes over; glucose is broken down into pyruvate without using oxygen. This system peaks at 15 seconds.

outer smooth membrane of the mitochondria

works with the inner membrane to regulate what enters and leaves the mitochondria

aerobic system (glucose)

Glycolysis occurs but pyruvic acid is by product, not lactic acid. This involves Krebs cycle; NO by products and more energy is created, by passing electrons through the transport chain. At 55 seconds, aerobic system is DOMINANT and takes over.

Function of fats (lipids)

Important source of energy in recovery periods, physically protects vital organs, controls body temperature, assists in hormone synthesis, cell membranes and transports fat-soluble vitamins

how does insulin affect glycogen formation

Insulin stimulates glycolysis, gluconeogenesis is inhibited, glycogenesis is promoted, lipolysis is inhibited and protein synthesis is promoted

Function of vitamins

Regulate energy release, co-factors in various chemical reactions

Distinguish between saturated and unsaturated fatty acids

Saturated: no double or triple bonds between carbons; unsaturated: 1 or more double or triple bonds in the fatty acid chain

rough endoplasmic reticulum

System of internal membranes within the cytoplasm. Membranes are rough due to the presence of ribosomes. functions in transport of substances such as proteins within the cytoplasm

explain the role of ATP in muscle contraction

actin and myosin in muscle fibers use ATP to provide chemical energy to drive the contraction process (only 2 seconds worth)

major sites of triglyceride storage

adipose tissue and skeletal muscles

which energy system is mainly used by endurance athletes

aerobic glucose/fatty acid systems - both the other two systems are used but not "mainly"

anaerobic creatine phosphate system

1 PCr = 1 ATP, occurs quickly, max use of 20 seconds exercise, creatine is another by-product

Function of minerals and trace elements

Involved in processes for maintaining bone and blood health, release of energy, muscle function, maintenance of cellular fluid balance

State the composition of triacylglycerol

Is an ester composed of a glycerol bound to three fatty acids

Macromolecule with the most energy per gram

Lipids (fats)

Function of water

Medium for biochemical reactions, transports nutrients/metabolites/waste/hormones/gases, thermoregulation, excretion, cell-cell and cell-environment communication, lubrication of joints and other surfaces

Explain how glucose molecules can combine to form polysaccharides

Multiple monosaccharides can be linked to a disaccharide to form a polysaccharide (condensation reactions)

What is the origin of unsaturated fats?

Plant-based foods: olive oil, olives, avocado, peanuts, cashew nuts, canola oil, seed, sunflower oil, rapeseed

List the micronutrients

Vitamins, minerals, trace elements

Composes the greatest percent of body mass

Water

Water molecule

What is removed when a monomer joins to a polymer through a dehydration reaction