Exam 3

What substance does the uvula produce?

Mucus

What does mucus do?

lubricates the larynx

How many lobes does the right lung have?

3 lobes (superior, middle, inferior)

How many lobes does the left lung have?

2 lobes: superior and inferior

What cells make up the trachea?

pseudostratified ciliated columnar epithelium

What are aveoli?

Tiny sacks in the lungs that work in gas exchange

Conducting zone

trachea, bronchi, bronchioles, terminal bronchioles-conducts air, No gas exchange

Respiratory zone

-respiratory bronchioles to alveoli

-site of gas exchange

Path of O2 molecule

trachea, main bronchus, lobar bronchus, segmental bronchus, terminal bronchus, respiratory bronchus, alveolar duct, alveoli, blood

Elastin connective tissue

made of elastin fibers, stretches during inhalation, elastic recoil- expels air

What is bronchi cartilage made out of?

Hyaline cartilage

What role does smooth muscle play in bronchioles?

controls diameter of airways

What is the purpose of smooth muscle in airways?

to protect lungs and body against toxins and unwanted irritants

What cells make alveoli?

Simple squamous epithelium

type 1 pneumocytes

line alveoli, squamous, thin for optimal gas diffusion

type 2 pneumocytes

produce surfactant-not thin

surfacant

Lowers surface tension, preventing alveoli from collapsing

What is another name for alveolar macrophages?

dust cells

What does alveolar macrophages do?

phagocytize inhaled debris

What is quiet respiration

involuntary, relaxed

What is forced respiration

deep or rapid breathing

involuntary

(exercising, sneezing, coughing)

Inspiration

breathing in (inhalation), muscles create slight vacuum in lungs

Expiration

breathing out (exhalation)-Rebound of chest wall and elastic connective tissue creates pressure inside lungs

What makes up the respitory membrane

squamous alveolar cells, basement membranes, capillary endotheial cells

What is happening to the diaphragm during inspiration

the diaphragm is being pushed downwards-contraction

What is happening to the diaphragm during inspiration

the diaphragm is going back up-relaxation

Where do the ribs go during inspiration?

ribs swing forward and outwards

What do we breathe in

78% nitrogen, and 20% oxygen

What increases saturation(solubility)

temperature and pressure

What are the two types of metabolic waste?

products of catabolism(aerobic respiration and amino acid catabolism) and excess substances

What is uric acid

breakdown of nucleic acids

What can happen if uric acid crystalizes?

it can causes kidney stones and gout

What is another name for kidney stones?

renal calculi

What are the four types of kidney stones

calcium oxalate, calcium phosphate, uric acid, cysteine

What do you excrete from your integumentary system?

sweat, sebum , salts, urea, and lactate

Where does the renal artery come from?

abdominal aorta

Where does the renal vein go to?

inferior vena cava

What is the function of a nephron

filtration of blood , reabsorption of nutrients, secretion of wastes

How many collecting ducts are in each renal pyramid

about 6

What is the pathways of urine

collecting duct, papillary duct, minor calyx, major calyx, renal pelvis, ureter, then urinary bladder

Where does the interlobar artery and vein go through

they go through the renal columns

does the segmental artery have a corresponding vein

no

where is the arcuate artery and vein located

on the border of the cortex and medulla

What makes the renal tubule

PCT, nephron loop, DCT, and collecting duct NOT the renal corpuscle

What is the glomerular capsule made of

Epithelium- parietal layer- simple squamous, visceral layer-podocytes

What are the two kinds of nephrons

cortical and juxtamedullary

cortical nephrons are..

short, located mostly in the cortex, and makes up 85% of nephrons

juxtamedullary nephrons are

long nephron loops that deeply invade medulla and concentrate urine (retain water)

What is the purpose of the kidneys

to excrete wastes, some hormones, and foreign substances (drugs)

What do the kidneys regulate?

blood volume, blood pressure, blood osmolarity, electrolyte balance,

What endocrine functions does the kidney do

erythropoietin- red blood cell production, calcitriol- calcium homeostasis, renin-increases blood pressure

What other function does the kidney perform

gluconeogenesis

What is step one of urine formation

glomerular filtration- plasma like filtrate formed from blood- cells and proteins stay in blood

Step 2 of urine formation

tubular reabsorption- removes useful solutes from the filtrate and returns them to the blood

Step 3 of urine formation

tubular secretion- removes add. wastes from the blood, adds them to the filtrate (uric acid, drugs, hydrogen ions etc)

Step 4 of urine formation

Water conservation removes water from the urine and returns it to blood, concentrates wastes

What are the three parts of the glomerular filtration membrane

fenestrated endothelium of capillary, basement membrane, filtration slits

What drives filtration out of the glomerulus

net filtration pressure

Glomerulus Blood Hydrostatic pressure

Very high-60 mmHg

Afferent diameter is greater than efferent diameter

Glomerulus Filtration Rate (GFR)

Too fast- not enough reabsorption (loss of water, electrolytes etc)

Too slow- wastes are reabsorbed

How is glomerulus filtration rate controlled

Myogenic mechanism

Tubuloglomerular feedback

What is the purpose of the myogenic mechanism

To stabilize the GFR, regardless of systemic bp fluctuations

stimulates stretch for smooth muscle contraction(afferent arteriole)

if the systemic blood pressure increases then..

the afferent arteriole constricts

if the systemic blood pressure decreases then..

the afferent arteriole dilates

What are the three parts of the juxtaglomerular apparatus

Mascula densa, extraglomerular mesangial cells, and granular cells

What is the macula densa

patch of sensory cells- part of the ascending limb epithelium

they sense the levels of NaCl in the tubular fluid

What happens when the Glomerulus filtration rate is too high?

that means there's too much sodium chloride in the blood (not enough reabsorption) this means the Macula densa secretes ATP

What are the two types of mesangial cells

Extraglomerular mesangial cells and intraglomerular mesangial cells

What is the function of intraglomerular cells

phagocytosis

membrane filtration

support capillaries

can constrict capillaries to reduce GFR

Granular cells

aka juxtaglomerular cells

smooth muscle cells that wrap around the afferent arteriole

What signal constricts the granular cells

adenosine

What do extraglomerular cells do?

convert ATP into adenosine (paracrine signaling)

What is the PCT made out of

Simple cuboidal epithelium

has many microvilli to increase surface area which increases absorption

lots of mitochondria

What is the DCT made of?

simple cuboidal- few microvilli

What does the PCT (proximal convoluted tubule) absorb from the filtrate?

65% is water and electrolytes

100% Glucose, amino acids, vitamins ions

What are the two routes of PCT reabsorption

Transcellular- (active transport)primary and secondary, passive transport

Paracellular- Through tight junctions, passive transport

What gradients is used for PCT reabsorption

Sodium/Potassium pumps

colloid osmotic pressure (after the glomerular filtration)

Which part of the nephron loop is thick?

Descending of the PCT

Which part of the nephron loop is thin?

Ascending of the DCT

What is solvent drag

solutes carried by movement of solvent. This is when solutes get reabsorbed into the blood

How is glucose transported into and out of the cell during the transcellular route of the PCT

Into the cell- secondary active diffusion (sodium glucose transporter)

out of the cell- facilitated diffusion (sodium potassium pump)

What is happening to the hydrogen ions during the transcellular route of the PCT

They are being transported out of the cell by the sodium/hydrogen antiporter. This helps with acid-base balance

What is happening to chloride during the transcellular route of the PCT

chloride is being reabsorbed into the the tubular fluid by the chloride/ anion antiporter and into the peritubular capillary through the potassium/chloride symporter (both leaving the cell)

How is water being transported during the transcellular route of the PCT

It is going through the passive process of osmosis out of the cell. Water is being transported into the cell rom the tubular fluid through the uses of aquaporins

What is transport maximum?

Maximum rate at which glucose can be reabsorbed from the tubules

What is glucosuria

high blood sugar leading to excess glucose in the urine

Is the collecting duct permeable to water?

yes; has lots of water channels (aquaporins)

is the collecting duct permeable to solutes?

nope, this helps concentrate the urine

Is the descending limb permeable to water

Yes, but not Na+ or Cl-, K+

is the ascending limb permeable to water

No, it is impermeable. NaCl diffused out

What is the function of the nephron loop?

to reabsorb some water and to maintain osmotic gradient in the medulla

What percentage of osmolarity does urea make in the medulla

40%

What is urea permeable to?

the lower collecting duct

the descending limb of the nephron loop

How does urea diffuses

it goes from the collecting duct into the descending limb

What is the purpose of the gradient

to concentrate urine and reabsorb water

How is water gain/loss regulated

through thirst, urine, and water in poop

Why is peeing important

to excreate nitrogenous wastes

What causes azotemia?

too much nitrogenous wastes in the blood due to kidney failure

What are some causes of water imbalances

Dehydration, diabetes mellitus ( excess glucose) and diabetes insipidus (ADH hyposecretion)