BIOL 2160 Final notecards

What three things are the kidneys primarily responsible for?

Maintaining stability of ECF volume, electrolyte composition, and osmolarity

What is the other function of the kidneys?

They are the main route for eliminating potentially toxic metabolic wastes and foreign compounds from the body

True or False: The main job of the kidneys is to produce perfect urine.

FALSE. It is to MAKE PERFECT BLOOD by filtering out impurities and making sure blood comp. is correct

What is responsible for maintaining the H20 Balance in the body?

Kidneys

What does the urinary system consist of?(KUUU)

Kidneys, Ureters, Urinary bladder, Urethra

What is the Ureter?

A smooth muscle-walled duct that carries urine to the urinary bladder

What is the purpose of the bladder?

To store urine

What is the urethra?

A tube that carries urine from the bladder to the outside of the body

True or False: The urethra is much longer in males than females.

TRUE

What are the two functions of the urethra in men?

Carry urine out of the Body and semen from reproductive organs

What is a nephron?

The microscopic structural and functional unit of the kidney

What is the dominant part of the vascular component of nephrons?

The glomerulus

What is the glomerulus?

A ball of capillaries that filters blood as it passes through

What is the tubular component made up of?

A hollow fluid filled tube formed by a single layer of epithelial cells (LEAKY for EXCHANGE)

What four basic processes does urine result from?

Glomerular filtration, tubular reabsorbtion, tubular secretion, concentration

Filtrate is formed during what renal process?

Glomerular filtration

Fluid gets filtered from the glomerulus into ______.

Bowman's Capsule

What is tubular reabsorption?

Things going from the tubule to the capillaries(urine to blood)

True or False: Tubular Reabsorption is a highly selective and variable process.

TRUE.

What are the steps of tubular reabsorption?

1.Substance Leaves tubular fluid by crossing luminal membrane of tubular cell
2.Passes through cytosol from one tubular cell to the other
3. Crosses basolateral membrane of the tubular cell to enter interstitial fluid
4. Diffuses through interstitial fluid
5. Penetrates capillary wall to enter blood plasma

What is passive reabsorption?

No energy is required for the substance's net movement

What is active reabsorption?

Occurs if ANY ONE STEP of the ENTIRE PROCESS of the substance's movement requires energy

True or False: If four of the five steps of tubular reabsorption are passive, then overall it is a passive process.

FALSE. One active step makes it all active

Is sodium reabsorption a passive or active process?

ACTIVE

What is essential for Na+ reabsorption?

An active Na+ - K+ ATPase pump in basolateral membrane

Of the total energy spent in the kidneys, what percent is used for Na+ transport?

80%

True or False: Na+ is NOT reabsorbed in the descending loop of henle.

TRUE

How does water follow reabsorbed sodium?

Osmosis, which affects blood volume and blood pressure

What percent of sodium is reabsorbed in the proximal tubule?

67%

What role does the proximal tubule play in Na+ Re-absorption?(Reabsorbs GACHU)

Reabsorbs glucose, amino acids, H20, Chlorine, and Urea

What percent of Na+ is absorbed in the Ascending loop of henle?

25%

What role does the ascending loop of henle play in Na+ Reabsorption?

Plays a critical role in kidney's ability to produce urine of varying concentrations

What percent of sodium is reabsorbed in the distal and collecting tubules?

8%

What role do the distal and collecting tubules play in Na+ Reabsorption?

Play a role in regulating ECF volume

During tubular reabsorption, what is the most important thing reabsorbed?

SODIUM

What part of sodium reabsorption is active and which is passive?

Overall it is ACTIVE.
Lumen membrane is passive
Basolateral is ACTIVE
Capillary is passive

The active transport of sodium occurs when sodium _____.

Crosses the basolateral membrane

Glucose and amino acids are reabsorbed by what type of transport?

Sodium Dependent, Secondary Active Transport

The reabsorption of water into the blood surrounding the proximal tubule increases the concentration of urea ______.

INSIDE THE TUBULE because water is lost from the tubule.

What produces a concentration gradient for urea from the tubule into the interstitial fluid?

The reabsorption of water into the blood surrounding the proximal tubule

What substance is reabsorbed that is TOXIC?

Urea.

How does the PASSIVE process of reabsorption of urea work? *END OF PROXIMAL TUBULE

Urea gets reabsorbed along with all the sodium, amino acids, and water we need at the END OF THE PROXIMAL TUBULE

What is tubular secretion?

Transfer of substances from peritubular capillaries into the tubular lumen (Blood to Urine)

What type of transport does tubular secretion involve?

Trans-Epithelial Transport

True or False: The kidneys can selectively add some substances to the filtrate.

TRUE

True or False: Everything secreted is NOT harmful.

TRUE. Too much of anything is a BAD thing

What is H+ important for in tubular secretion?

Regulating the acid-base balance

Where is H+ secreted?

Proximal, Distal, and Collecting tubules

What is K+ important for in tubular secretion?

Keeping plasma K+ concentration at a normal level to MAINTAIN NORMAL MEMBRANE EXCITABILITY in muscles and nerves

Where is K+ secreted?

Distal and collecting tubules only

Where are organic ions secreted?

Only in the Proximal tubule

The more protons in our urine, the ____ our pH.

LOWER

What process allows drugs to be detected in urine samples?

Tubular SECRETION

True or False: Urine has a relatively high pH.

FALSE. It is relatively LOW

What is concentration?

The maintenance of a large osmotic gradient around the Loop of Henle that allows water to be retained and urine to be HIGHLY concentrated

What is the purpose of the Loop of Henle?

To concentrate your urine

Descending limb of loop of henle

HIGHLY permeable to water, NOT permeable to Na+. Water gets reabsorbed

Ascending limb of loop of henle

HIGHLY permeable to NaCl, NOT permeable to water. SODIUM gets reabsorbed

Where does Vasopression controlled, variable water reabsorption occur?

In the distal tubule and collecting duct

True or False: The re-absorption of water is obligatory.

TRUE. NOT voluntary

What is vasopressin?

ADH. Antidiuretic hormone.

What does vasopressin do?

When dehydrated, it inserts aquaporins into the distal tubule membrane. This makes it VERY permeable to water. Water then leaves the distal tubule and gets reabsorbed. At the end, urine is SUPER CONCENTRATED

Where is vasopressin produced?

In the Hypothalamus

Where is vasopressin stored?

Posterior pituitary gland

For every 250 ml of alcohol consumed, your body eliminates how much water through your urine?

1000mLs. THIS CAUSES THE HANGOVER

Alcohol is an ADH inhibitor. What does this cause?

Causes your body to get rid of water in the form of urine

What is urine stored in the bladder eliminated by?

Mucturition- ACT OF URINATING

What is the feeling of needing to urinate caused by?

Stretch receptors being stimulated in the bladder

What is urinary incontinence?

Involuntary loss of urine because your muscles cannot contract strong enough to keep you from peeing

What are the four things broken down in the digestive system? (FSPN)

Fats ,sugars, proteins, nucleic acids

What is the primary function of the digestive system?

Transfer nutrients, water, and electrolytes from ingested food into body's internal environment

What are the four functions of the digestive system?(MADS)

Motility- Moves food around
Secretion- Releases certain hormones/juices/acids
Digestion-Mechanical (Chewing), Chemical(Enzymes)
Absorption- Absorbing into Bloodstream

Motility

Muscular contractions that mix food and move forward the contents of the digestive tract

What are the two types of digestive motility?

Propulsive movements and Mixing movements

Propulsive Movements

Push contents FORWARD through the digestive system

Mixing Movements (2 parts)

-Mixing food with digestive juices (back and forth)
-Facilitates absorption by exposing all parts of intestinal contents to absorbing surfaces of digestive tract, mainly small intestine

What do secretions consist of?(WEE)

Water, electrolytes, and ENZYMES

What are secretions?

Secretions are released into digestive tract lumen and are normally reabsorbed back into blood after their participation in digestion

What is digestion?

Biochemical breakdown of structurally complex foods into smaller, absorbable units

How is digestion accomplished?

By enzymatic hydrolysis

When digested, carbohydrates are broken down into

monosaccharides

When digested, proteins are broken down into

Amino acids

When digested, fats are broken down into

Glycerol AND fatty acids

Where is most absorption completed?

SMALL INTESTINE. It is the organ for absorption

What takes place during absorption?

Small units resulting from digestion, along with water, vitamins, and electrolytes are transferred from digestive tract lumen into blood

True or False: The digestive tract is continuous from the mouth to the anus.

TRUE

What does the digestive tract consist of?
(MPESSLA)

Mouth
Pharynx
Esophagus
Stomach
Small Intestine
Large Intestine
Anus

True or False: In the digestive tract, food goes DIRECTLY into the components.

TRUE. DOES NOT go directly into accessory organs

What are the accessory digestive organs? (SEBLG)

Salivary Glands
Exocrine Pancreas
Bilary System:
Liver & Gallbladder

What are the four major tissue layers of the digestive tract from INNER to OUTER?

Mucosa- faces lumen
Submucosa
Muscularis Externa- layer of muscle
Serosa- outer layer

What is the function of mucosa?

It lines the innermost surface of the digestive tract. Its highly folded surface increases absorptive area

What is the submucosa?

A THICK CONNECTIVE TISSUE that provides the digestive tract with ELASTICITY

What is the Muscularis Externa?

A major SMOOTH MUSCLE coat of the digestive tube

What are the two layers of the muscularis externa?

Circular layer (INNER) and Longitudenal layer (OUTER)

What is the function of the circular layer?

Contraction DECREASES diameter of lumen
For propulsive movements ***

What is the function of the longitudinal layer?

SHORTENS LENGTH OF TUBE through contractions
For MIXING and ABSORPTION

What is directly responsible for the propulsive and mixing movements?

The circular and longitudinal layers of the Muscularis Externa

What does the Serosa do?

SECRETES SEROUS FLUID

What are the two functions of the fluid secreted by the serosa?

Lubricates and prevents friction between organs and viscera to keep them from damaging
Supports organs in proper place while allowing them freedom for movements. Allows them to FLOAT

What are the 3 characteristics of your lips? (FHW)

Form opening of mouth
Help procure, guide,and contain food in mouth
Well-developed tactile sensation