Bio 1a Physiology

What are the main char of diffusion?

- greater [ ] diff : faster - single cell / simple animals depend on

Define Smooth muscular tissue

- involuntary & non-striated - aka visceral - basal dilate & contract - ex: diaphragm

What are the shared char of connective tissue?

- origin of Mesenchyme/Mesoderm (np, can signal intracellularly) - range of vascularity: ligaments (almost no blood supply / slow to heal) Vs. blood - all have an extracellular matrix (ECM) which provides a stable outside enviro

What is the rete mirabile?

-a network of blood vessels traveling through the body (usually found in warm-blooded animals) -key to T reg in homeotherms -aka countercurrent heat exchangers

List levels of change organisms go through to maintain homeostasis / their set point

-acute: constant T (mech to reduce/increase in response to environ) -chronic: acclimation to new environment -evolutionary: genetic changes (EPAS1 for Nepalese to breathe) -developmental: puberty

Define connective tissue

-cells in extracellular matrix (ECM) -hold tissues/organs together or in place -fibroplasts, cartilage, bone, blood

Define nervous tissue

-conductive & irritable -recieves, processed, and transmits info -unique to animals

Define muscular tissue

-contractile (due to protein actin/ myosin) & irritable (respond to stimulus) -body movement -unique to animals

Define cuboidal epithelium

-cube shaped, secretion

What is the relationship between body size and... a) BMR (what is BMR?) b) O2 consumption

-every process/reaction in body gives off some heat a) inverse relation (large = slow,) bc larger SA:Vol ratio to lose heat through -BMR = basal metabolic rate b) linear relation (large O2 consumption)

Define Adherens junction

-more "basal" than the tight junction -bridge neighboring cytoskeletons

Define stratified epithelium

-multi-layered, protection -typically quickly regenerative

What are the shared char of epithelial tissues?

-polar -shared contacts -support connective tissue -avascular (no blood flow/ vessels) BUT innervated (has nerves through it) -regenerative

Define glandular meaning with reference to exocrine and endocrine processes.

-secreted out -exo: via a vein -endo: through chem messengers & hormones

Define basal surface

-side facing basal/basement membrane

What is a simple epithelium and its benefit?

-single layer -great for diffusion

What is the TNZ

-thermoneutral zone -range of ambient T where homeotherms are able to maintain a constant metab rate

Define epithelial tissue

-tissues with a "free surface" -acts as a barrier, sensory function, absorptive, secretive (covers the body, fills a cavity, lines a tube)

What issues arise with SA:Vol ratios?

-when body size increase, this decreases (s^3 vs. 6s^2) -more difficult to deliver nutrients/gases and remove waste (fast enough / large amounts for cell)

Name the three phases of gastric secretion

1) Cephalic 2) Gastric 3) Intestinal

Effects of diabetes mellitus

1) Fat becomes main substrate for cell respiration 2) Acid metabolites accumulate in blood, lowering blood pH. 3) [Blood glucose] exceeds capacity of reabsorption by kidney. 4) [Urine glucose] causes excess H2O in urine by osmosis. 5) Copious urine

List the essential nutrients

1) Omega 3 & Omega 6 FA. 2) 8 AAs. Histidine essential for children. 3) Vitamins (small amt) 4) Minerals/inorganic nutrients (small amt)

Ingredients that make up saliva

1) Salivary amylase 2) Lingual lipase 3) Bicarbonate 4) Mucins (lubricant) 5) Lysozyme & IgA

What are the 4 functions of the circulatory system

1) Transport 2) Stabilize internal pH 3) Contribute to body temperature regulation 4) highways for phagocytes

what are the two main nervous tissue elements?

1. Neurons (nervous cells): -axon tail & transistors -"workers" 2. Neuro-glia: -support cells : nourish, insulate, or mod neurons -"band-aids"

List key human responses to INC in T:

1. Sweat! 2. Vasodilation / basal dilation to vent heat

List key human responses to DROPS in T:

1. behavioral thermoregulation 2. Vasoconstriction (tightening of vessels) via sympathetic nerve action 3. Pilomoter response: goosebumps, inc insulation 4. Shivering thermogenesis (NOT FOR BBs) 5. Non-shivering thermogenesis: brown fat mitochondria has proton uncoupling (H+ flow creates heat, not ATP) - in adults along spinal cord - BBs only hope

List the main 3 connective tissue elements

1. ground substance: hydroxylated gels of proteoglycans & hyaluronic acid -proteoglycans = proteins + GAGs -gels rapidly diffuse water-soluble molecules but inhibits the movement of large molecules and bacteria 2. fibers: embedded in ground sub - collagen: inc. tinsel & pull strength 3. Cells: Fibroblasts - "blasts" : immature, forming sites - "cytes" mature - can interchange

What percentage of total body weight is blood?

6-8%

What is an example of an advantage of a closed circulatory system over an open circulatory system?

Able to control the flow of blood

What cells secrete glucagon? Where?

Alpha cells in pancreas.

What cells secrete insulin? Where?

Beta cells in pancreas.

Why do diets fail?

Body is responding to perceived starvation. Metabolic rates slow by 45% & lean tissues are preferentially lost; as fat is lost reduced leptin signaling to hypothalamus stimulates release of NPY that induces feeding, decreases energy expenditures, inhibits growth & reproduction

Veins always carry (which type of blood, where?)

Both kinds of blood (pulmonary veins carry oxygenated blood), towards the heart.

Compare Brown & White Fat:

Brown: - fat consumed through Crebs cycle -proton gradient formed as proton uncoupling occurs in Brown mito -NO atp syn - heat prod from H+ flow White: -E stores of lipids (help make ATP) - White --> Brown : through cold conditions and exercise

Define intestinal phase:

chyme enters small intestine. This inhibits gastric secretion via secretin and CCK.

Define tight junctions

connections between tissues; used to keep objects from passing in interstitial fluid between cells (and instead through the tissue itself)

A newborn baby left in the cold would respond physiologically by (2 answers)

cutaneous vasoconstriction & non shivering thermogenesis in brown fat tissue (babies can't shiver!)

Define squamous epithelium

flattened, cross small distances easily

Compare homeothermy and poikilothermy

homeo: constant T reg, V expensive ( allows higher levels of activity / wide range of habitats) poikilo: T fluxes with environment

What is the human energetic paradox?

humans have both highest BMR and highest Reproduction rate per size

Define Cardiac muscular tissue

involuntary & striated (banded)

Define parotid gland

largest salivary gland. Beside the ear. (The word parotid literally means 'beside the ear')

When leptin levels are low, the hypothalamus releases _____ which ______

neuropeptide Y (NPY); stimulates feeding, decrease energy expenditure, inhibits growth & reproduction

Which type of photoreceptor is most sensitive to dim light? Where is this located in the retinal layer?

Rods; periphery.

Define submandibular gland

Second largest salivary gland. Situated below the jaw. (The word submandibular literally means "below the jaw)

The Na+/K+ pump creates an electrochemical gradient. This enables the sodium glucose transporter to import glucose against its concentration gradient in brush border cells. The transport of glucose is an example of_______

Secondary active transport

Where, and by what mechanism, are lipids digested?

Small intestine, by pancreatic lipases.

Define sublingual gland

Smallest salivary gland, located anterior to the submandilar glands. (Sublingual literally means 'below the tongue')

When secretin and CCK are secreted from the small intestine, what is the effect on the liver, gallbladder, and pancreas?

Stimulation of bicarbonate production in the pancreas. Stimulates bile production in liver. Stimulates bile release from gallbladder.

When gastrin is secreted from the stomach, what effect does it have?

Stimulation of the parietal cells to secrete HCl. Stimulates gastric motility.

Define the gastric phase:

Stomach pressure activates stretch receptors in stomach that trigger reflex responses. Triggers release of gastrin. Gastrin triggers release of HCl and pepsinogen. Gastrin triggers peristaltic contractions.

What is the effect of insulin? What organ does it target?

Targets liver, increases uptake of glucose (and storage of glucose as glycogen)

Difference between Type 1 and Type 2 Diabetes

Type 1 (Insulin dependent) is an autoimmune disorder. The pancreas doesn't produce enough insulin. Can be cured with insulin injections. Type 2 (Insulin independent) target cells become insensitive (resistant) to insulin. Associated with obesity and lack of exercise.

What is the fundus?

Upper cavity of the stomach. Peristalsis.

What is the tightening of the blood vessels? What is its effect?

Vasoconstriction: Increases blood pressure. Increases body temperature.

What is the relaxing of the blood vessels? What is its effect?

Vasodilation: Decrease blood pressure. Decrease body temperature.

What is chyme

acidic mixture of proteins, gastric juice, partially digested stuff.

Leptin is secreted by ____

adipose cells

Describe an RBC

anucleate (no nucleus); without mitochondria (rely on anaerobic metabolism) carry hemoglobin.

Describe platelets

Fragments of cytoplasm wrapped in plasma membrane; lifespan of about a week; involved in clotting; derived from megakaryocytes

Name the 3 parts of the stomach

Fundus, body, antrum

What cells release gastrin? From where?

G cells, from the mucous lining of the stomach.

What would we expect to be secreted between meals?

Glucagon

Why does acid reflux happen?

Humans lack a true sphincter muscle at stomach opening. Food can easily move back up into esophagus.

When plasma glucose levels rise, insulin secretion ______, lysis of glycogen in the liver _____, and utilization of glucose by neurons _____.

Increases; decreases; stays the same.

When secretin and CCK are released from the small intestine, what is the effect on the stomach?

Inhibition of parietal cells (stops HCl)

Where are cuboidal epithelium most likely to be found

Kidney and glands

What is the antrum?

Lower cavity of stomach. Connects to pyloric sphincter.

What is the body of the stomach?

Main portion.

Which biological sex has more RBCs?

Male

Compare negative feedback inhibition and positive feedback

Neg: a control mech that reduces a stimulus (ex work out inc T -- sweat to reduce T) Pos: amplifies a signal to drive to completion

Compare neural and endocrine systems

Nervous System: -signal w/ neurons -nerve impulse travels along axon to location -response: lim by cells that connect by specialized junctions Endocrine: -signal w/ hormones (from endocrine cell) - hormones travel via bloodstream / vessels -response: lim by cells that have hormone receptor needed

Is natural diffusion rapid enough to supply somatic cells with Oxygen?

No. This is why we need a circulatory system.

Trace the path of food through the body

Oral cavity > oropharynx > laryngopharynx > esophagus (over epiglottis > stomach > pyloric sphincter > duodenum > jejunem > ileum > ileocecal sphincter > large intestine (over cecum) > rectum > anus > freedom

In the stomach ____ is secreted from ____ cells. It is activated by ____ secreted by ____ cells.

Pepsinogen; chief. HCl; parietal

What makes up the majority of the volume of blood?

Plasma

The chemical digestion of which food FIRST begins in the stomach?

Protein

What is an erythrocyte?

RBC

What cells are in the blood?

RBCs, WBCs, Platelets

What is the function of leptin?

Regulator of appetite, satiety factor (Suppresses appetite).

What is an example of an open circulatory system over a closed circulatory system?

Requires less energy cost

Define columnar epithelium

secretion and active absorption

What is basal restriction and when is often seen?

the discarding of extremity(s) to protect core system (brain / heart) functionality; hypothermia

Define apical surface

the side of the tissue that faces the lumen, outside, or free surface

In homeotherms, ______ relay info through the body, spinal cord, brain, & scrotum to the ____

thermosensitive neurons, hypothalamus

Define the cephalic phase

triggered by smell, taste, sight, etc. Cerebral cortex of CNS sends nerve impulses (vagus nerve) to stimulate gastric glands.

Define Skeletal muscular tissue

voluntary & striated (banded)

What is peristalsis

Contraction and relaxation of digestive muscles that moves food around

Which is true of hemoglobin? 1) Carries O2 2) Carries CO2 3) assists in buffering blood 4) Exhibits cooperativity 5) All of the above

5

What is the total volume of blood in the human body?

5-6 Liters

What could a human be most considered? A) endothermic and homeothermic B) endothermic and poikilothermic C) ectothermic and homeothermic D) ectothermic and poikilothermic

A

_______ intestinal epithelial cells function in secretion of synthesized proteins and the trans-epithelial transport of important nutrients whereas _____ epithelial cells are better suited as endothelial cells in capillaries.

Columnar; squamous

Compare conforming and regulating animals

Conformers: -internal cond. is aligned w/ external cond. Regulators: -maintain Homeostasis (w/ constant T) -aligns with "set point" -Negative Feedback Inhibition -typical of higher lifeforms -metab expensive $$$

Define diabetes mellitus

Cells unable to absorb glucose from blood.

Pepsin serves what function? Where?

Degrades proteins into small polypeptide chains. Stomach.

What do bile salts from the gallbladder do? Why?

Emulsify fat globules to increase the surface area for lipases to digest them.

What is plasma consisted of?

Water, proteins, ions, sugars, lipids, AAs, hormones, vitamins, gases, wastes.

Define cooperativity as it relates to enzymes and hemoglobin

When a substrate binds to one site, affinity for the substrate at other sites is increased.

Compare endothermy and ectothermy

endo: the internal generation of heat, higher metabolic rates (usually larger SA:Vol, higher heat loss rates) ecto: gain heat from external sources, thermal regulation via behavior mech