IB A.2.1-2 Quiz

Potassium (K_⁺)dominates salt in

Intracellular Fluids (ICF)

Sodium (Na+) dominates salt in

Extracellular (ECF)

Active Transport requires

ATP

Water balance changes are detected in the

hypothalamus

When detecting water balance changes(dehydration) the hypothalamus…

1. activates sensation of thirst

2. produces Antiduretic hormone (ADH) which causes the kidneys to retain fluids and reduce urine production

Osmoregulation

regulation of water content in blood

Excretion

Filter solutes out blood, then use cellular transport mechanisms to regulate what stays in the urine and what should return to the blood.

Each kidney is made of 1.25 million…

nephrons

Glomerulus

filters various substances from the blood, has fenestrations (small slits) that open under high blood pressure. 

Bowman’s Capsule

filters blood and collects the resulting filtrate to begin urine formation

acts as a cup-shaped structure that surrounds the glomerulus

Ascending Limb of the loop of Henle

Na+, K+, and 2 Cl- reabsorber into cells or bloodstream

Proximal Conviluted tubule

Selective reabsorption of Sugars, amino acids, and Na+ into cells or bloodstream

What structures are in the Outer Medulla?

Descending limb of LOH, Loop of Henle, Acending limb of LOH, Collecting duct

What structures are in the Cortex?

Glomerulus, Proximal convoluted tubule, Distal convoluted tubule

Distal convoluted tubule

see image

What structures ultrafiltrates

Bowman’s Capsule

What structures selective reabsorb

Proximal Tubule, Distal Tubule

What structures osmoregulate?

Loop of Henle(salt gradient), collecting duct(water retention)

Each nephron contains a very small branch of the renal artery known as an afferent arteriole.

This very small artery brings unfiltered blood to the nephron. 

Inside the Bowman's capsule, the afferent arteriole branches into a specialized capillary bed called the glomerulus.

efferent arteriole

drains blood from the glomerulus & has a smaller diameter than the afferent arteriole.

Ultrafiltration

the process by which various substances are filtered through the glomerulus (& its fenestrations) under high blood pressure in the capillary bed.

portal system of circulation

a series of veins that connect two capillary beds, allowing blood to flow from one set of capillaries to another before returning to the heart

Microvilli

microscopic projections found only in the plasma membrane portion facing the lumen of the tubule.

Lumen

the hollow space or cavity inside a tubular structure, such as a blood vessel, intestine, or organelle

Uric acid

a complex & energy- requiring molecule to produce but it is not toxic to living tissues bc it is insoluble in body fluids.

Urea

the molecule produced by organisms that have to make a compromise between toxicity & the need for temporary storage of a waste product (such as urine in mammals).

Desending Loop of Henle

permeable to water but relatively impermeable to mineral ions. 

Permeable

allowing liquids or gases to pass through it

Impermeable

NOT allowing liquids or gases to pass through it

Ascending Loop of Henle

is relatively impermeable to water but permeable to mineral ions.

Little water is reabsorbed if…

blood solute concentration is low

Osmoregulators

organisms that expend energy to maintain a homeostatic internal solute concentration.  

Osmoconformers 

organisms whose solute concentration is similar to that of the environment.  

hyponatremia

low plasma concentration of sodium

Hypernatremia

occurs when there is a deficit of total body water relative to total body sodium content. 

Cardiovascular drift

phenomenon characterized by a rise in heart rate & a fall in stroke volume over time during exercise

Macronutrients

nutrients that our body needs in large amounts to maintain health.

These include:

• Carbohydrates

• Fats

• Proteins

• Water

undernutrition

hunger

malnutrition

vitamin defiency

overnutrition

obesity

Recomended macronutrients per day of carbohydrate

50-60%

Recomended macronutrients per day of protein

12-15%

Recomended macronutrients per day of fat

less than 30%

Micronutrients

vitamins, minerals, trace elements

Anabolic reactions

Uses energy to  build complex molecules (polymer chains) from simpler ones.  They do so through condensation reactions. These reactions remove water (H₂O) between monomers & then form a new covalent bond. 

Catabolic reactions

break down complex molecules into simpler ones, which releases energy.  They do so through hydrolysis. Hydrolysis is the opposite of condensation. Polymers are broken down by adding H₂O & breaking covalent bonds.

Condensation reaction

reactions that remove water between monomers and then form a new covalent bond.

Hydrolysis

Polymers broken down by adding H2O and breaking covalent bonds

Carbohydrates

Made up of C, H, O

are organic compounds synthesized by plants from water & CO₂ using solar energy.

100g of carbohydrate = 1760kj

Monosacchrides

single sugar molecules

glucose, fructose, gluctose

Disaccharides

form when 2 monosaccharides link together through condensation

Sucrose

formed from glucose and fructose

lactose

formed from galacose and glucose

maltose

formed from 2 gluose monomers

Oligosaccharides

form when 3-9 sugars are joined together through condensation.

ex. maltodextrin

Polysaccharides

form when 10 or more sugars are joined togetherthrough condensation

ex. glycogen, starch, cellulose

dietary fiber

poorly digestible, found in cell walls of plants, plays role in prevention of disease

intake of 100g or fat+ 4,000kj

Fatty Acid

chains of carbon atoms with hydrogen attached, and a methyl group (CH3) + carboxyl group (COOH) on each end

Saturated Fatty Acid

have a maximum number of C-H bonds. So they only have single-covalent bonds and a relatively linear.

Unsaturated fatty acid

have double covalent bonds which affects their shape

Monounsaturated

only one double bond

Polyunsaturated

multiple double bonds

Omega-3 Fatty acids

Polyunsaturated’s that have the first double bond located between the 3rd and 4thcarbon atom form the mathyl end

Omega-6 Fatty acid

Polyunsaturated that have thrie first double bond located between the 6 and 7th carbon atom from methyl end.

Triglyceride

molecules are the main component of fats & oils.  

• They are formed through the condensation of three fatty acids & glycerol. 

• They are broken down & stored in adipose tissue. 

• Joined by an ester linkage between the -COOH of the fatty acid & the -OH of the alcohol.

Steroid

Lipids with four fused rings.

• Cholesterol

• Sex hormones

Proteins

the second most abundant compounds in the body. 

• Water is the most abundant

• Contain atoms of C, H, O, N, (S)

Proteins are made of monomers called

amino acids (AAs). 

Intracellular

it acts as a medium for vital biochemical reactions.

Extracellular

• Transport of nutrients, metabolites, waste products, hormones, & respiratory gases.

• Thermoregulation (sweat) & excretion (urine, feces).

• Cell-cell & cell-environment communication

• Lubrication of joints & sliding surfaces. 

Vitamin D 

produced through precursors in the skin in combination with sunlight.

Vitamin B (niacin)

synthesized from the AA tryptophan.