Biology--MCAT
Monohybrid trait
a cross in which only 1 trait is being studied
inclusive fitness
a measure of an organism's success in the population, based on the number of offspring, success in supporting offpsring, and the ability of the offspring to then support others.
Isotype switching
cells change which isotope of antibody they produce when stimulated by specific cytokines
Cell migration
cells must be able to disconnect from adjacent structures and migrate to their anatomically correct location Ex: anterior pituitarygland originates from secment of ORal ECtoderm, migrates from top o outh to just below hypothalamus -neural crest cells micrate from edge of neural folds to rest of body(sensory ganglia, autonomic ganglia, adrenal medulla, schwann cells, others
pluripotent stem cells
cells that can differentiate into any cell type except for those found in placental structures -more specialization leads to multipotent
multipotent stem cells
cells that can differentiate into multiple types of cells within a particular group Ex: hematopoietic stem cells diff into all cells found in blood including RBCs, WBCs, platelets...
Anaphase II
centromeres divide -so chromosomes are separated into sister chromatids -chromatids are pulled to opp poles by spindle fibers
What increases glucagon release from alpha-cells?
certain gastrointestinal hormones (cholecystokinin and gastrin)
What domains of life contain bacteria?
archaea and bacteria
envelop (prokaryote
cell wall +plasma (cell) membrane
paracrine signals
cell-cell signals that act on cells in the LOCAL area
autocrine singlas
cell-cell signals that act on the SAME cell the secrete the signal
Juxtacrine signals
cell-cell signals that do NOT usually involve diffusion, but involve a cell directly stimulating receptors of an adjacent cell
endocrine signals
cell-cell signals the involve secreted HORMOES that travel through the bloodstream to a DISTANT target tissue
stratum spinosum
cells become connected to each other site of Langerhans cels
enteric nervous system
collection of 100 million neurons that govern the function of the gastrointestinal system present in walls of digestive tract and trigger PERISTALSIS (rhythmic contractions of the gut tube, in order to move materials through the system) -can function INDEPENDENTLY of brain and spinal cord --although it is heavily regulated by the autonomic nervous system
semen
combo of sperm and seminal fluid
the accessory organs of digestion orginate from which primary germ layer?
endoderm
What do lysosomes often function in conjunction with
endosomes (which transport, package, and sort cell material travelling to and from the membrane) endosomes can transport material to the trans-golgi, to the cell membrane, or to the lysosomal pathway for degradation
What is the bulk of the pancreas made of?
exocrine cells = ACINAR CELLS -responsible for pancreatic juices -contains enzymes that work on all 3 classes of biomolecules -pancreatic amylase -pancreatic peptidase -pancreatic lipase
that determines the physical and biochemical characteristics of every living organism?
genes: DNA sequences that code for heritable traits that can be passed from one generation to the next
endochondral ossification
hardening of cartilage into bone responsible for most of the long bones in the body
myoglobin reserve
high O affinity, as exercising muscles run out of O, they use myoglobin reserves to keep aerobic metabolism going fast
glomeruli
highly convoluted capillary tufts derived from afferent arterioles location: Bowman's capsule
what happens when the immune system misidentifies harmless material as harmful?
hypersensitivity reactions (allergies)
why does cleavage officially create an embryo?
it nullifies the unicellularity of the zygote (defining feature)
where does muscular contraction start?
neuromuscular juction this is where the nervous system communicates to the muscle via MOTOR (efferent) Neurons
How does the posterior pituitary receive input?
neurons in the hypothalamus send axons down pituitary stalk directly into the posterior pituitary (can release OXYTOCIN and ANTIDIURETIC HORMONE)
Where is endocrine tissue found in the GI tract?
stomach and intestine secretin gastrin cholecystokinin
Rectum
storage site for feces (indigestible material, H2O, bacteria, certain digestive secretions that are not reabsorbed (enzymes, bile)
chromosomal mutation
larger-scale mutations in which large segments of DNA are affected
Telophase II (Stage 9)
nuclear membrane forms around each new nucleus cytokinesis follows -2 daughter cells formed -up to 4 haploid daughter cells are produced per gametocyte
What surrounds the nucleus of a cell?
nuclear membrane or envelope--double membrane that maintains a nuclear environment separate and distinct from the cytoplasm -has nuclear pores
how do fats enter systemic circulation
packaged into lipoproteins (water sol) bypass hepatic portal via throacic duct
what does pancreatic anylase break down?
pancreatic amylase breaks down large POLYSACCHARIDES into small disaccharides -responsible for carbohydrate digestion
What nerve is responsible for much of the parasympathetic innvervataion of thoracic and abdominal cavity?
vagus nerve (CN X)
skeletal muscle
voluntary somatically innervated straited due to sarcomeres (repeating units of actin and myosin) multinucleated
when does edema occur?
when the lymphatics are overwhelmed with fluid so the fluid collects in the tissue
renal pelvis
widest part of the ureter, spans almost the entire width of the renal hilum
what is the pressure differential equation?
Delta P = pressure differential across the circulation CO = cardiac output TPR = total peripheral (vascular) resistance
In adults where does GH have its primary effects?
Smaller bones, causes ACROMEGALy -long bones are sealed, so can't really affect them
glottis
Opening between vocal cords covered by epiglottis
Cytotoxic T-cells
"CTL" cytotoxic lymphocyte CD8+ capable of directly killing virally infected cells by injecting toxic chemicals that promote apoptosis into the infected cell
antibody
"immunoglobulin" Ig can be present on surface of cell or secreted in body fluids -When antibody binds to antigen, reaction depends on location (if antibody secreted into body or cell-surface antibodies)
Thrombocytes
"platelets" -cell fragments or shards released from cells in bone marrow known as MEGAKARYOCYTES -purpose: assist in Blood Clottin -concentrated 150,000-400,000/microL -
regeneration
"regenerative capacity" -the ability of an organism to regrow certain parts of the body (varies on species) -COMPLETE Regeneration: the lost or damaged tissues are replaced with identical tissues INCOMPLETE regeneration: implies that the newly formed tissue is not identical in structure or function to the tissue that has been injured or lost --------Humans display this
Adaptive immunity
"specific immunity" defenses that target a specific pathogen -slower to act than innate, but can maintain immunological memory of an infection to mount a faster attack in subsequent infections -B-cells -activated B-cells secrete antibody molecules tha bind to antigens -T-cells
osmotic pressure
"sucking" pressure generated by solutes as they attempt to draw water int the bloodstream usually attribute to plasma proteins ("oncotic pressure")
What do monocytes do?
(agranulocytes) --phagocytize foreign material (bacteria) -most organs have collection of monocytes --> macrophages Ex: microglia, langerhans, osteoclasts
what are the layers of the dermis?
(in dermis there are sweat glands, blood vessels, and hair follicles that originate in dermis) papillary layer (upper layer) -loose CT reticular layer
What happens if there is low perfusion of the juxtaglomerular cells?
(in kidney) -stimed release o aldosterone through renin-angiotensin-aldosterone system -increases reabsorption of Na (and therefore water) -OVERALL: increases blood volume and pressure
transposons
(jumping genes) short strands of DNA capable of moving from one location to another within a cell's genetic material, they can insert and remove themselves from the genome. -if a transposon inserts in the middle of a coding sequence, the mutation will disrupt the gene
Renin-angiotensin-aldosterone system
(pg 175) 1. decreased BP casues juxtaglomerular Kidney cells to secrete RENIN 2. Renin cleaves an inactie plasma protein (angiotensinogen) to active form (angiotensin I) 3. Angiotensin I --> angiotensin II -Angiotensin Converting enzyme (ACE) (in lungs) 4. Angiotensin II stims adren l cortex to secrete ALDOSTERONE 5 Neg feedback. BP decreases, drive to stim renin decreases = neg feedback
what is cartilage primarily made of?
(softer and more flexible than bone) firm, but elastic matrix called CHONDRIN that is secreted by cells called CHONDROCYTES -fetal skeletons mainly made of cartilage -AVASCULAR, NOT innervated
How can carrier proteins change the levels of ACTIVE hormone?
(steroid hormones) -When hormones attached to carrier, they are INactive -must Dissociate to activate -So level of protein carriers can change the levels of ACTIVE hormone Ex: condition can increase quantity of protein that carries THYROID hormones (Thryroxine-binding Globulin (TBG) -body perceives lower level of thyroid hormone becuase increased TBG binds larger portion of hormone (less free hormone ava)
T-cells are agents of ...
***Cell-mediated immunity***...because they coordinate the immune system and directly kill virally infected cells
What are some common second messengers?
- Cyclic AMP -Inositol Triphosphate (IP3) -Calcium
What are some of the important functions of calcium in the body?
- bone structure and strength -release of neurotransmitters form neurons -regulation of muscle contraction -clotting factor (Ca is a COfactor) (also role in cell movement and exocytosis of cellular materials)
What can cause HYPOthyroidism?
-deficiency of Iodine -Inflamm in thyroid
starling forces
- hydrostatic and oncotic pressures -balance of these forces maintains proper fluid volumes & solute concentrations inside & outside the vasculature -Imbalance of these pressures results in too little or too much fluid in tissues
What does the ovum contribute to the zygote?
-1/2 DNA -all the cytoplasm -organelles (including mitochondria) -RNA for early cellular processes Sperm only donates 1/2 DNA
Anaphase
-3rd stage of mitosis -Centromeres split -each chromatid has its own distinct centromere (this allows separation) -sister chromatis are pulled toward the opp poles of cell by shortening the kinetochore fibers
Telophase and Cytokinesis
-4th stage of Mitosis -Telophase = reverse of prophase -spindle apparatus disappears -nuclear membrane reforms AND nucleoli reappear -Chromasomes UNCOIL (resume interphase form) -each of 2 new nuclei receive a complete copy of genome identical to original and each other Cytokinesis occurs at end of telophase
What is the normal range of partial pressure of O2 in the blood?
-70-100mmHg
how does ADH influence high blood osmolarity
-ADH (peptide hormone) (from hypothalamus/POSTerior pituitary) -released when high blood osmolarity -alters permeability of collecting duct, allowing more water to be reabsorbed by making cell junctions of duct leaky
Luteal phase
-After ovulation, LH causes ruptured follicle to form CORPUS LUTEUM, which secretes PROGESTERONE -Progesterone levels rise while estrogen remain high -High progesterone causes NEG feedback on GnRH, LH, and FSH which prevents ovulation of multiple eggs
What type of cells do the pancreas's Islets of Langerhans contain?
-Alpha---secrete Glucagon -Beta----secrete Insulin -Delta---secrete somatostatin
What happens upon B-cell exposure to the correct antigen?
-B-cells will proliferate and produce two types of daughter cells 1. plasma cells -produce large amounts of antibodies (eventually die) 2. memory B-cells -stay in lymph node awaiting reexposure to the same antigen Initial exposure.activation take 7-10 DAYS = PRIMARY RESPONSE
Pancreas
-BOTH EXOcrine and ENDOcrine functions - EXOcrine tissues -secrete substances directly into ducts -ENDOcrine -produces hormones -Hormone-producing cells (Islets of Langerhans grouped together) -produces many digestive enzymes
Explain how the RBC carried CO2
-CO2 diffuses into RBC -Carbonic anhydrase catalyzes the combination reaction between CO2 and H2O to carbonic acid (H2CO3) -carbonic acid will dissociate into a proton and a bicarbonate anion (both have high solubility in H2O making them more effective method of transporting metabolic waste products to lungs) -arrival at lungs reverses rxns, releases CO2
characteristics of gram-pos bacteria
-CW thick layer of peptidoglycan ([polymeric substance made from AA and sugars) -lipoteichoic acid
Why does diffusion between maternal circulation and fetal circulation work?
-Diffusion requires a gradient -implies that there is a greater higher partial pressure of O2 in Maternal blood than there is in fetal blood -Fetal hemoglobin (HbF) also has a greater affinity for oxygen than maternal hemoglobin (HbA) -This also aids retention of O2 in fetal circulatory system
what are the other enzymes or hormones the duodenum secretes?
-ENTEROPEPTIDASE: involved int eh activation of other digestive enzymes from the accessory organs of digestion hormones -SECRETIN (regs H2O homeostasis, produced in S cells of duodenum) -CHOLECYSTOKININ (CCK) (mediates digestion by inhib gastric emptying)
What causes RE-POLARIZATION?
-Efflux of K+ -Overshoots causing HYPER-polarization
What are the 3 shunts in a fetal heart?
-Foramen Ovale = bypass LUNGS -moves blood from R atrium to L atrium -one way valve. Vena cava to RV flow to LV -R side of heart higher pressure in infants -Ductus Arteriosus -shunts leftover blood from the pulmonary artery to the aorta -ductus venosus -shunts blood returning from the placenta via the umbilical vein directly into the inferior Vena Cava (liver receives some blood supply from smaller hepatic arteries in the systemic circulation
MIcroglia
-Glial cells -Phagocytic cells that Ingest and Breakdown Waste products and Pathogens in CNS
Inhibitory input
-HYPERPOLARIZATION -(lowers membrane potential from resting) -LESS likely to fire
Anatomy of sperm
-Head: covered by cam called ACROSOME (structure is derived from the Golgi apparatus and is necessary to penetrate the OVUM) -Midpiece: filled with mitochondria (generate energy for swiming through the female repro tract to reach ovum in fallopian tubes) -Tail: flagellum (motility) -avg male produces approx 3 million sperm per day after puberty
What happens in the first trimester?
-Heart beat at 22 days -then eyes, gonads, limbs, and liver begin to form -5 wks embryo = 10 mm -6wks = 15 mm -7th wk, cartiliginous skeleton hardens -8th wk, most organs formed, brain fairly developed and embryo = fetus -end 3rd month, 9 cm long
What preserves the corpus luteum in the 1st trimester of pregnancy?
-Human Chorionic Gonadotropin (hCG) preserves the corpus luteum in the 1st trimester
Intermediate filaments
-Keritin, desmin, vimentin, lamins...ect -cell-cell adhesion -maintenance of overall integrity of cyskeleton -can withstand lots tension, help strucutral rigidity of cell -ANCHOR organelles (& nucleus) -Identity of inter. fil. proteins in a cell is specific to cell and tissue type
Ovualtion
-Late in follicular phase, dev follicles secrete higher conc (increasing) of estrogen --Estrogen levels reach threshold-->POS feedback so GnRH, LH, and FSH levels spike -Spike in LH induces OVUALTION = release of ovum from ovary into peritoneal cavity -progesterone decreases
Neurtrophil
-MOST populous leukocyte in blood -VERY short-lived (little over 5 days) -Phagocytic, and target bacteria -can Follow bacteria--chemotaxis -can detect bacteria that have been opsonized ( marked with an antibody from a B-cell) -dead neutrophils are responsible for the formation of pus during an infection.
smooth ER
-NO ribosomes -mainly for lipid synthesis (ex: phospholipids in cell membrane) and DETOXIFICATION of certain drugs and poisons -also transports proteins from the RER to the golgi apparatus
Impulse Propagation
-Na rushing in causes depolarization to surrounding regions and bring subsequent secitons to threshold. AP continues in wave -like fashion -after firing, segment becomes refractory ensuring info flow in ONLY ONE direction
how does the synapse expel neurotransmitters?
-Neurotransmitters are stored in membrane-bound vesicle in nerve terminal -AP reaches terminal, causes Ca2+ channels to open and allow Ca to flow into cell -increase in intracell Ca causes fusion of membrane-bound vesicles with cell membrane at synapse (EXOCYTOSIS)
How does the notochord induce further neurulation?
-Notochord induces a group of overlying ECTOdermal cells to slide inward to form NEURAL FOLDS -Those Neural Folds then surround a NEURAL GROOVE
fiber types of skeletal muscles
-RED fibers/slow-twitch fibers -high myoglobin content and primarily aerobic -many mitochondria --? oxidative phosphorylation -WHITE fibers/ Fast-twitch fibers -less myoglobin--> less Fe --> less color can be MIX of BOTH
What activates the sympathetic nervous system?
-STRESS -increases HR -redistributes blood to muscles of locomotion -increases blood glucose conc -relaxes bronchi -decreases digestion/peristalsis -dilates eyes (increase light) -releases epi into bloodstream
Characteristics of EUkaryotic cell
-Unicellular or Multicellular -contain NUCLEUS -membrane bound organelles (phospholipid bilayer) endocytotic vesicle centrioles nucleolus nuleus golgi apparatus ER ribosomes cytoplasam mitochondrion cell membrane nuclear membrane
draw the bicarbonate buffer system
-What would an increase in H+ ions cause? -increase in CO2
macrophages
-agranulocyte -resides in tissues -can become RESIDENT pop (become permanent cell group in tissue)
what proteins does the liver synthesize?
-albumin--a protein that maintains plasma oncotic pressure and serves as a carrier for many drugs/hormones -clotting factors used during blood coagulation
what was the original form of cell theory?
-all living things are composed of cells -the cell is the basic functional unit of life -cells arise only from preexisting cells Fourth tenant added later -cells carry genetic information in the form of deoxyribonucleic acid (DNA). This genetic material is passed on from parent to daughter
Which two pancreatic hormones are the major drivers of glucose homeostasis?
-alpha-cells which produce glucagon to increase glucose concentration -beta-cells decrease blood glucose concentration
Characteristics of PROkaryotic cell
-always SINGLE celled -NO nucleus -DNA in circle in nucleoid region -simplest/include ALL bacteria fa
Interneurons
-assisting -located predominately in brain and spinal cord and often linked to REFLEXIVE behavior -reflexes only require processing at level of spinal cord (not brain)
Menstruation
-assuming implantation didn't occur -corpus luteum loses stim form LH -progesterone levels decline -uterine lining is sloughed off -Loss of high levels o estrogen and progesterone removes block on GnRH so that next cycle can begin
Which 2 types of cells, if not properly functioning will make an individual most susceptible to a CNS infection?
-astrocytes -microglia
polysynaptic reflex arc
-at least one interneuron between sensory and motor neurons Ex: withdrawl reflex (stepping on nail) has to stim multiple muscle groups on both legs to allow retraction from stim and to balance
gallbladder
-below liver -stores/concentrates bile -CCK release causes gallbladder to contract and pushes bile into BILIARY TREE -bile duct merges with pancreatic duct and empties into duodenum
During what developmental stage is there the greatest nuclear-to-cytoplasmic ratio?
-blastula has the greatest number of cells during development the cells are displaced from the center by the blastocoel
What do mixed nerves carry?
-both Sensory and Motor info
peroxisomes
-breakdown long chains in Beta-Oxidation -participate in synthesis of phospholipids -contain catalase used in PPP -contain hydrogen peroxide
eosinophils
-bright red-orange granules -primarily involved in ALLERGIC rxns -activation --> release lots of HISTAMINE(inflammatory mediator) -result: vasodialtion and increased leakiness of blood vessels (allows immune cells (esp macrophages and neutrophils) to move out of blood stream and into tissues)
what is the path of blood flow for the pulmonary arteries?
-capillaries get deoxygenated blood from PULMONARY ARTERIE (form R side of heart) -oxygenated blood returns to L atrium of heart via PULMONARY VEINS
Excitatory input
-causes DEPOLARIZATION (raising membrane potential Vm, from resting potential) -MORE likely to fire -Reaches -55mV to -40mV TRIGGERS AP
all bacteria contain...
-cell membrane -cytoplasm -some have flagella or fimbriae (similar to cilia) bacteria outnumber human cells 10:1 (bacteria in gut produce vit K) -can live intra/extracellularly
G2 Stage: prostsynthetic Gap
-cell passes through another quality control checkpoint -Cell check: make sure enough organelles and cytoplasm for 2 daughter cells. DNA replicated correctly (G2/M checkpoint) -p53 also plays a role -to M stage
S stage: synthesis of DNA
-cell replicates genetic material so that each daughter has identical copies -after replication, each chromosome consists of 2 identical CHROMATIDS (bound by CENTROMERE) -ploidy of cell doesn't change even though number of chromatids has doubled (humans still have 46 chromosomes even though they have 92 chromatids at this stage) -goes to G2 (with 2x as much DNA as G1) -(there are 92 chromatids organized into 46 chromosomes, which are organized into 23 homologous pairs)
G1 stage: Presynthetic Gap
-cells create organelles for Energy and protein production (mitochondria, ribosomes, ER) -increase in size -the to restriction point and S phase
viral envelope
-composed of phospholipids and virus-specific proteins (encapsulates capsid) -sensitive to: heat, detergents and desiccation -enveloped viruses are easier to kill
Basophil
-contain large purple granules -involved in ALLERGIC response (release histamine) -LEAST populous leukocyte in under normal conditions
What is an antigen-binding region and what is at the end of it?
-contains Variable region (domain) -region has specific polypeptides that will bind ONLY ONE specific antigen sequence
Nucleus
-contains all genetic material necessary for replication
Reflexive arcs
-control reflexive behaior -signal goes to spinal cord and interneurons in cord send signal back target tissue. sensory info goes to brain, but already responded to pain 1. monosynaptic reflex arc 2. knee-jerk reflex
sweating
-controlled by AUTONOMIC nervous system -body temp rises above set by hypothalamus, postganglionic sympathetic neurons that utilize Acetylcholine innervate sweat glands and promote secretion of water in certain ions onto skin -phase change -arteriolar vasodilation occurs to max heat loss -brings large V blood to skin
epithelial tissues
-cover body andl ive cavities -protect aginst pathogen invasion and desiccation -involved in absorption, secretion, and sensation -one cohesive unit -cells tightly joined to each other and to basement membrane -in most organs, =parenchyma (functional parts of organ) -often polarized (faces in other side out)
creatine phosphate
-created by transferring a phosphate from ATP to creatine during times of rest -this rxn can be quickly reversed during muscle use to quickly generate ATP from ADP
Amino Acid-Derivative hormones
-derived from 1 or 2 amino acids w/ additional modifications (thryroid hormones made from tyrosine and modified by addition of several iodine atoms) -Include epinephrine, norepinephrine, triiodothyronine, and thyroxine -Catecholamines (epinephrine and norepinephrine) bind to G protein coupled receptors --> fast onset & short lived -Thyroid hormones bind intracellularly (slower onset & longer duration) (thyroxine and triodothyronine...reg metabolic rate over a long period of time) -Have names that end in -in or -ine (thyroxine)
What maternal conditions can also influence the child?
-diabetic women/hyperglycemia -overexposure to sugar in utero --> fetus too large to deliver that suffers from hypoglycemia after birth -maternal folic acid deficiency - may prevent complete closure of neural tube
What does the resting membrane potential depend on?
-differential distribution of ions across the axon membrane -active transport of ions across membrane
Where is the thymus located and what does it do?
-directly behind the sternum -releases THYMOSIN - important for proper T-cell development and differentiation -thymus atrophies by adulthood, and thymosin levels drop accordingly
Somatic nervous system
-division of PNS, consists of Sensory and Motor neurons distributed through skin, joints, and muscles -
male reproductive system
-ductus deferens = vas deferens
Pregernert (pregnancy)
-fertilization occurred zygote-->blastocyte-->implant uterine lining --> secrete Human chorionic gonadotropin (hCG) -Human chorionic gonadotropin: analog of LH. chem similar and can stim LH receptors. -hCG MAINTAINS corpus luteum
flagella anatomy
-filament: hollow helical structure that anchors the flagellum and composed of FLAGELLIN -basal body: complex structure that anchors the flagellum to cytoplasmic membrane an is the motor of flagellum (rotates 30 Hz) -hook: connects filament and basal body so that basal body rotates. It exerts torque on filament which spins and propels bacterium forward.
symtpoms of HYPERthyroidism
-heightened activity level -increased body temp -increased RR and HR -heat intolerance -weight loss
What happens after the sperm contacts the corona radiata and zona pellucida?
-first sperm to contact secondary oocyte's cell membrane forms a tubelike structure = ACROSOMAL APPARATUS - this apparatus extends to and penetrates the cell membrane -pronucleus may then freely enter oocyte once MEIOSIS II is completed
mentral cycle key concepts
-follicles mature during follicular phase (FSH, LH) -LH surge at midcycle triggers ovulation -Ruptured follicle becomes corpus luteum, which secretes estrogen and progesterone to build up uterine lining in prep for implantation; LH an dFSH are inhibited -if fert doesn't happen, corpus luteum atrophies, progesterone and estrogen levels decrease, menses occurs, and LH and FSH levels begin to rise
what do the seminal vesicle contribute?
-fructose to nourish sperm and some alkaline properties to seminal fluid
what are the 4 main anatomical divisions of the stomach?
-fundus and body: contain mostly gastric glands -antrum and pylorus: contain mostly pyloric glands
what type of glands does the mucosa of the stomach contain?
-gastric glands -pyloric glands
list similarities of Mitosis and MEIOSIS
-genetic material must be duplicated -chromatin Condensed to form chromosomes -microtubules emanating from centrioles are involved in DIVIDING genetic material
What happens to hormones in the second trimester?
-hCG levels decline -progesterone levels rise (now secreted by the placenta -high levels of progesterone and estrogen inhib GnRH (which prevents FSH and LH secretion and the onset of a new menstrual cycle
how to bile salts aid in digestion?
-have hydrophobic and philic ends -EMULSIFY fats and cholesterol into micelles -makes them accessible to pancreatic lipase (water sol) -increase surface area of fats, increases rate at which lipase can act
microtubules
-hollow polymers of tubulin proteins -tubules radiate through cell providing primary pathways along which motor proteins (KINESIN and DYNEIN) carry vesicles -compose cilia (movement of materials along surface of cell) and flagella (movement of the cell itself)
What are the two pressure gradients that are essential for maintaining a proper balance of fluid volume and solute concentrations between the blood and the interstitium?
-hydrostatic pressure -osmotic pressure
starling forces at the capillary bed
-hydrosttic pressure greater than oncotic pressure -net efflux of water from the circulation at arteriol end -as fluid movs out of vessels, hydrostatic pressure drops significantly....osmotic pressure stays about same -oncotic pressure above hydrostatic at venule end NET INFLUX
centrioles
-in centrosome -organizing centers for microtubules -strucutred as 9 triplets of MICROTUBUlES with hollow center -move to opp poles of cell during mitosis when dividing cell. also organize mitotic spindle
What functions to EPI and NE perform?
-increase HR -Dilate bronchi -shunt blood flow for sympathetic response
What are the effects of EPI?
-increase breakdown of glycogen to glucose (glycogenesis) in LIVER and MUSCLE -increase basal metabolic rate -increase HR -dilate bronchi -shunt blood for sympathetic response -vaso-dialte for skeletal muscle, heart, lungs, brain
What are alternative causes of a right shift in the oxyhemoglobin dissociation curve?
-increased temperature -increased 2,3-bisphosphoglycerate (2,3-BPG) (side product of glycolysis in RBCs)
What causes Type I diabetes?
-insulin-dependent diabetes -caused by AUTOIMMuNE destruction of Beta-cells in pancreas -causes low in absent insulin production require injections to allow uptake of glucose in cells
from beginning of loop of henle to end, is there dilution or concentration?
-isotonic at beginning then hypotonic, so slight dilution -volume of filtrate is significantly reduced
Id curves of stomach
-lesser curvature -greater curvature
What characterizes HYPOthyroidism?
-lethargy -decreased body temp -slowed RR and HR -cold intolerance -weight gain -appropriate levels of T3 and T4 are crucial for neurological and physical development
What happens in the second trimester?
-lots of growth -moves within amniotic fluid -face looks human -fingers/toes elongate -end of 6 month 30-36 cm long
Peptide hormones
-made of AA -range in size 1. ALL derived from larger precursor polypeptides that are cleaved during posttranslational modification 2. then smaller units transported to Golgi for modifications that activate hormone and direct them to correct locations in cell 3. released via EXOCYTOSIS
how is BP measured?
-measures pressure above and beyond atmospheric pressure systolic (ventricular contraction) diastolic (ventricular relaxation)
Where does the sperm meet the oocyte and what happens when they meet?
-meet: Ampulla-widest part of fallopian tube -sperm binds to oocyte and releases acrosomal enzymes that enable the head of the sperm to penetrate the CORONA RADIATA and ZONA PELLUCIDA
M Stage: Mitosis
-mitosis and cytokinesis -Mitosis: Prophase, Metaphase, Anaphase, Telophase Cytokinesis: splitting of the cytoplasm and organelles between 2 daughter cells
Are most x-linked disorders dominant or recessive?
-most X-linked disorders are recessively inherited -so females express X-linked disorders far less frequently than males -females who carry diseased allele on X-chromosome but don't exhibit disease, are CARRIERS
nephron filtration
-movement of solutes form blood to filtrate at bowman's capsule -20% of blood that passes through glomerulus is filtered as fluid into Bowman's capsule -fluid that is collected = filtrate -movement of fluid governed by STARLING FORCES - HYDROstatic pressure in glomerulus is significantly higher than in Bowman's space (causes fluid to move INTO nephron) -oncotic pressure opposes this hydrostatic pressure since osmolarity of blood is higher than capsule -net flow into capsule since hydrostatic pressure is higher than oncotic
PNS
-nade up of nerve tissue and fibers OUTSIDE of brain and spinal cord -includes all 31 pairs of spinal nerves -10 of the 12 pairs of cranial nerves -connects CNS to rest of boy -divided into autonomic and somatic
besides myogenic activity, what other systems play a role in the regulation of cardiac muscle contraction?
-nervous system -vagus nerve --> PNS --> slows HR -endocrine system -NE from SNS or epi from adrenal medulla binds to ANDRENERGIC receptors in heart --> increased HR + increased contractility
What causes Type II diabetes
-non-insulin dependent -result of receptor-level resistance to the effects of insulin -partially inherited, and partially due to enviro factors (high-carb diets, obesity)
Name female gonads and hormones they produce
-ovaries: contain thousands of FOLLICLES (multilayered sacs that contain, nourish, and protect immature OVA (eggs)) -produce estrogen and progesterone
Autonomic nervous system
-part of the PNS -regulates Heartbeat, respiration, digestion, and glandular secretions -involuntary muscles associated with internal organs/glands -Regulates body temp (sweating) INDEPENDENT of Conscious control -preganglionic neuron (in CNS, axon travels to ganglion in PNS) then to Postganglionic neuron (Synapses if pregang. and stims target tissue)
What are the chemical identity classifications of hormones?
-peptides -steroids -AA derivatives
What stimulates salivary glands?
-presence of foods in oral cavity triggers neural circuit that increases parasympathetic stimulation -or smell/sight of foo
anatomy of synapse
-presynaptic neuron -postsynaptic neuron -"effector" if signals to gland/muscle instead of other neuron -usually synapses = chemical in nature
What does the loss of Helper T cells result in?
-prevents immune system from mountin adequate response to infection EX: occurs in HIV. in advanced HIV (AIDS), weak pathogens can cause horrible infections
hemoglobin
-primary carrier of O2 in th eblood -4 cooperative subunits -binding of O occurs at heme's central Fe atom
what is the function of the liver?
-processing and synthesis of nutrients -glycogenesis, glycogenolysis, storage and mobilization of fats, gluconeogenesis -production of urea -detoxification of chemicals -production of bile -synthesis of albumin and clotting factors
What type of cell displays MHC Class II molecules?
-professional antigen-presenting cells (ex: macrophages, dentritic cells (skin), come B-cells, and certain actived epithelial cells) (pick up pathogens from environment and present them) EXOGNOUS pathway
Positive selection of T cells
-refers to allowing on the the maturation of cells that can respond to the presentation of antigen on MHC (if no response to MHC, then apoptosis because they will not be able to respond in the periphery)
Mast cells
-related to basophils -have smaller granules and exist in tissues, mucosa, and epithelium -mast and basophils release lots of HISTAMINE in response to allergens leading to inflamm responses
What are the endocrine functions of the pancreas?
-release of insulin, glucagon, and somatostatin (peptide hormones necessary for the maintenance of proper blood sugar levels) -hormonal function of pancreas is limited to cells in Islets of Langerhans
Tropic hormones
-require an intermediate to act - usually originate in the BRAIN in or ANTERIOR PITUITARY gland b/c these structures are involved in coordination of processes within the body -cause release of another hormone at the organ level (stim production of another hormone by another endocrine gland that acts on theses target tissues) -GnRH causes release of FSH and LH which act on the gonads (testes and ovaries) -CRF (corticotropin-releasing hormone) causes release of ACTH which acts on the adrenal cortex -TRH (thyrotropin-releasing Hormone) causes release of TSH which acts on the thyroid
cooperative binding
-results in sigmoidal curve -In lungs, O diffuses into alveolar capillaries -as first O binds to a heme group, it induces a conformational shift in shape of hemoglobin from tense to relaxed which increases hemoglobin's affinity for O making it easier for subsequent O molecules to bind to remaining 3 unoccupied heme groups -as other heme groups acquire O, affinity increases (+ feedback mechanism) -Once all of the hemoglobin subunits are bound to O, the removal of 1 O induces conformational shift decreasing affinity for O making it easier for other O molecules to leave the heme groups -as O molecules leave, it becomes progressively easier for more O to be removed
what does lipase do?
-salivary enzyme -catalyzes the hydrolysis of lipids
Metaphase
-second phase of mitosis -centriole pairs are now at opp ends of cell -kinetochore fibers interact with fibers of spindle apparatus to align the chromosomes at the METAPHASE PLATE (equatorial plate) which is equidistant from the 2 poles of the cell
Mineralcorticoids
-secreted from adrenal cortex -used in salt and water homeostasis -MAJ effect on KIDNEYS Ex: ALDOSTERONE -increases Sodium reabsorption in distal convoluted tubule and collecting duct of nephron -Water follows Na so plasma osmolarity is unchanged - decreases reabsorption of potassium and hydrogen ions in same segments of nephron .....promoting excretion in urine
where do fats go from the epithelial cells?
-short-chain FA diffuse directly into intestinal capillaries -no transporter required, bec nonpolar -larger fats, glycerol, and cholesterol move separately into intestinal cells and then reform into triglycerides -triglycerides and esterified cholesterol packaged into chylomicrons -CHYLOMICRONS enter lymphatic circulation through LACTEALS
archaea
-single celled organisms that are visually similar to bacteria -contain genes and several metabolic pathways that are more similar to eukaryotes than bacteria -extremophiles, can be in human body -alt energy: chmosynthetic (generate energy from inorganic compounds such as S/N compounds), photosynthetic -resistant to many antibiotics -contain single circular chromosome, divide by binary fission or budding -similar overall structure to bacteria
monosynaptic reflex arc
-single synapse between sensory neuron (receives stim) and motor neuron (responds to stim) Ex: knee-jerk reflex (sensory to motor in spinal cord causes contraction)
actin
-solid polymerized rods of ACTIN -Organization: Bundles and networks -resistant to compression and fracture (provide PROTECTION for cell) -involved in Cytokinesis (division of materials between daughter cells) (forms cleavage furrow and pinches off dividing cells)
What are two key functions of lymphocytes?
-some are primary responders -others function to maintain the long-term memory bank of pathogen recognition
glucocorticoids
-steroid hormones regulate glucose levels -affect protein metabolism Ex: Cortisol and Cortisone -raise blood Glucose (increase gluconeogenesis, decrease protein synth) -decrease inflam and immunologic response Cortisol: released during stress to aid in blood glucose levels to react quickly Stim by ARF --> ACTH
Rough ER
-studded with ribosomes -ribosomes permit translation of proteins destined for secretion directly into its lumen
cytokinesis
-the separation of the cytoplasm and organelles, giving each daughter cell enough material to survive on its own -each cell undergoes a finite number of divisions before Programmed DEATH (human somatic cells usually 20-50 divisions) (no longer divides continuously after that)
What structures are part of gut-associated lymphoid tissue (GALT)
-tonsils -adenoids (in head) -peyer's patches (small intestine) -appendix (site of lymphoid aggregates)
How do peptide hormones travel?
-travel freely (w/o carrier) in bloodstream -water-soluble (steroids are only LIPID-soluble)
what ways can enveloped viruses enter a cell?
-tricking receptors (receptor mediated endocytosis) -direct fusion
What do astrocytes do?
-type of glial cell -nourish neurons and form the BBB (controls transmission of solutes from blood stream to nervous tissue)
Ependymal cells
-type of glial cells -line the ventricles of Brain--produce CSF
What collection of neurons regulate ventilation
-ventilation center -in medulla oblongata -fire rhythmically to cause regular contraction of respiratory muscles -contain CHEMORECEPTORs that are primarily sensitive to CARBOND DIOXIDE concentration
characteristics of gram-neg bacteria
-very thin -small amount peptidoglycan -wall and membrane separated by periplasmic space -have outer membranes that contain lipopolysacharides (these trigger immune system, inflamm response much stronger than response to lipoteihoic acid)
what is the small intestine lined with?
-villi--small fingerlike projections form epithelial lining -contains microvilli--drastically increasing the surfaace area available for absorption
Brain consists of...
-white matter and gray matter
What does hyper-polarization do?
1-makes neuron refractory to further AP 2 types refractory periods 1. ABSOLUTE refractory -NO amount of stim cause AP to occur 2. RELATIVE refractory -GREATER than Normal Stim to cause AP because membrane starting more NEG than normal
Why is the depolarization of the ovum after the cortical reaction important?
1. .depolarization prevents fertilization of ovum by multiple sperm cells 2. increased [Ca] increases the metabolic rate of the newly formed diploid ZYGOTE
Which 2 hormones are primarily involed in Ca homeostasis?
1. Calcitonin form parafollicular (C-) cells of thyroid -decreases blood calcium concentration 2. Parathyroid Hormone from parathyroid glands increases calcium concentration
what are the 4 basic tenants of the modern interpretation of Mendel's FIRST law (of segregation)
1. Genes exist in alternative forms (alleles) 2. an organism has 2 alleles for each gene--1 inherited from each parent 3. the 2 alleles segregate during MEIOSIS, resulting in gametes that carry only 1 allele for any inherited trait 4. If 2 alleles of an organism are different, only 1 will be fully expressed and other = silent. Expressed allele = dom, silent = recessive (codominance and incomplete dominance are exceptions to this rule) -during anaphase I of meiosis, separation (segregation) of chromosomes into different cells, each gamete carries only 1 allele for any given trait
What are the 6 products the stomach secretes?
1. HCl (kills microbes, denatures proteins, concerts pepsinogen into pepsin) 2. pepsinogen (cleaved in the stomach to pepsin; an enzyme that partially digests proteins) 3. mucus (protects mucosa) 4. bicarbonate (protects mucosa) 5. water (dissolves and dilutes ingested material) 6. intrinsic factor (required for normal absorption of vit B12)
Prophase I Zygotene
1. Homologous chromosomes come together and intertwine in a process called SYNAPSIS (each chromosome = 2 sister chromatids, so each synaptic pair contains 4 chromatids) -4 Chromatids = TETRAD 2. homologous chromosomes are held together by group of proteins called SYNAPTONEMAL COMPLEX
Besides nutrients/waste, what is the function of the placenta?
1. Immunity -fetus imunologically naieve, no exposure -accidental exposure happens in utero, crossing of antibodies over placental membrane = protective function 2. Placenta = Endocrine organ -produces progesterone, estrogen, and human chorionic gonadotropin (hCG) (all maintain preganncy)
what 2 sphincters does urine pass through to leave body?
1. Internal urethral sphincter: consists of smooth muscle, normal = contracted (involuntary) 2. External urethral sphincter: skeletal muscle, voluntary control
What two ratios are changed during embryo's rapid division?
1. N:C Nucleus to cytoplasm 2. surface area to volume so cells achieve increases are for GAS and NUTRIENT exchange relative to overall Volume
During action potential, which ion channel opens first and what are the effects?
1. Na+ opens first -closes around +35 mV -depolarizes cell 2. K+ opens second -closes at -70mV -re/hyperpolarization
What occurs once each month?
1. ONE egg is OVULATED into the PERITONEAL SAC (lines abdominal cavity) 2. egg is drawn up into FALLOPIAN TUBE (OVIDUCT) which is lined with cilia to propel egg forwar. 3. fallopian tubes connected to muscular uterus (site of fetal development)
What does the positive potential inside the cell trigger?
1. Voltage-gated Na channels INACTIVATE 2. trigger voltage-gated K channels OPEN -electrochem gradients favors EFFLUX ofk K
follicular phase
1. begins when menstrual flow (shedding lining of previous cycle) begins 2. increase in GnRH secretion from hypothalamus -response to decreased conc of estrogen/progesterone (fall off toward end of cycle) 3. High [GnRH] increase FSH and LH secretions 4. When follicles begin producing estrogen (NEG feedback loop) causes GnRH, LH, FSH to level off 5. ESTROGEN stims regrowth of the endometrial lining, stims vascularization and glandularization of DECIDUA
What are the mechanisms to regulate neurotransmitters outside cell?
1. break down of acetylcholine (ACh) via Achetylcholineesterase (AChE) 2. REUPTAKE carriers: bring neurotransmitters back into presynaptic neuron -reuptake of seratonin (5-HT), dopamine (DA) and Norepinephrine (NE) common 3. neurotransimtters diffuse out of synaptic cleft Nitric Oxide (NO) gaseous signaling Ex.
ways for progeny release
1. cell death due to invasion--degradation releases 2. too many viruses--lyse 3. extrusion--virus fuses with plasma membrane (essentially budding)
How does apoptosis occur?
1. cell morphology divides into many self-contained protrusions --APAPTOTIC BLEBS 2. these are broken apart into APOPTOTIC BODIES and digested by other cells (blebs are contained by a membrane which prevents the release of potentially harmful substances into extracellular enviro) Diff than necrosis necrosis -cell death due to injury -internal sub leaked causing irritation or an immune response
What are the 3 basic phases of birth?
1. cervix thins out.....Amniotic sac ruptures (water breaking) 2. strong uterine contractions result in birth of fetus 3. placenta and umbilical cord expelled (afterbirth)
Prophase I (Meiosis) LEPTOENE
1. chromatin condenses into chromosomes 2. spindle apparatus forms, and nucleoli and nuclear membrane disappear
What are the 2 ways the complement system can be activated/
1. classical pathway -requires the binding of an antibody to pathogen 2. alternative pathway -does not require antibodies
What are some ways a cell can become differentiated?
1. during cleavage where existing mRNA and protein in parent cell asymmetrically distrubed to daughter cells...Presence of mRNA and protein can result in determination 2. secretion of specific molecules from nearby cells -molecules = MORPHOGENS...may cause neighboring cells to follow specific dev pathway -concentration gradient, interact with other morphogens secreted other places
where do sperm travel through during ejacuulation?
1. through vas deferens 2. to ejaculatory duct (at posterior edge of prostate gland) 3. 2 ejaculatory ducts fuse to form urethra, which carrier sperm to penis and outside body -repro/urine are common pathway
What are the 2 cell groups of the blastocyst?
1. trophoblast 2. innercells -protrudes into the blastocoel and gives rise to the organism itself
what are the 2 divisions of the adaptive immune system?
1. humoral immunity (mainly B-cells) 2. cell-mediated (cytotoxic) immunity -each involves identification of the specific pathogen and organization of an appropriate immune response
What happens in the case of a Viral infection (intracellular)?
1. infected cell produces interferons (reduce the permeability of nearby cells, reduce transcription and translation in these cells, and cause systemic symptoms) 2. infected cells present intracellular proteins on surface via MHC-I (some of these surface proteins will be viral) 3. CD8+ (cytotoxic) cells recognize the MHC-I complex and antigen complex as foreign and Inject TOXINS to promote apoptosis (to stop infection before it spreads 4. If virus DOWNregulates the MHC-I receptors, then the NK will recognize the absence of the MHC-I and will cause apoptosis 5. memory T-cells will be generated
What are the two types of digestion?
1. intracellular digestion (part of metabolism) -involves the oxidation of glucose and FA for energy 2. extracellular digestion
list the 5 phases of prophase I
1. leptotene 2. zygotene 3. pachytene 4. diplotene 5. diakinesis
list some neurotransmitter receptors
1. ligand-gated....postsynaptic cell with be depolarized or hyperpolarized 2. G-protein coupled receptor -changes in either levels of cAMP or influx of Calsium
Why is ADH secreted?
1. low blood volume (baroreceptors) 2. increased blood osmolarity -targets collecting duct where it increases the duct's permeability to H2O -increases reabsorption of water from filtrate in nephron = greater H2O retention, increased blood volume, increased BP
What happens in the case of a bacterial infection (extracellular)?
1. macrophages (and other antigen presenting cells) engulf the bacteria and release inflammatory mediator 2. digest bacteria and present antigens via MHC II 3. the cytokines attract inflamm cells (neutrophils and more macrophages) 4. mast cells activated by inflammation and degranulate, resulting in histamine release and increased leakiness of capillaries 5. dendritic cell leaves affected tissue and travels to nearest lymph node where it presents antigen to B-cell. -B-cells that produce the correct antibody proliferate through clonal selection to create plasma cells and memory cells 6. antibodies travel through bloodstream to affected tissue where they tag bacteria for destruction 7. at the same time dendritic cells are also presenting antigen to T-cells, which activates the T-cells in response -specifically, CD4+ (Th1 and Th2) cells are activated 8. Th1 release interferon gamma (IFN-gamma) --> activatees macrophages and increases their ability to kill bacteria Th2 help activate B-cells and are more common in PARASITIC Infections 9.. Pathogen elimed --> cells die, but memory B and T cells remain
What are the lungs' defense mechanism against invaders?
1. macrophages: can engulf and digest pathogens and signal to the rest of the immune system that there is an invader 2. IgA antibodies (on mucosal surfaces). These help progect against pathogens tha contact the mucous membranes 3. mast cells. preformed antibodies are on surfaces so when right substance attaches, mast release inflamm chemicals to surrounding areas to promote immune reponse (sometimes to pollen, mold,)
differences between male/female meiotic process of gametocytes
1. no unending supply of stem cells analogous to spermatogonia in females -all of the oogonia a woman will ever have are formed during fetal development 2. by birth, all of the female oogonia have already undergone DNA replication and are considered PRIMARY OOCYTES. These cells are 2n, like primary spermatocytes, and are arrested in prophase I 3. once a woman reaches MENARCHE (1st menstrural cycle, one primary oocyte per month will Complete MEIOSIS I to produce a 2ndary OOCYTE and polar body -the secondary oocyte remains in arrest in METAPHASE II and does NOT complete the remainder of Meiosis II unless fertilization occurs
Prophase II (Stage 6)
1. nuclear envelope dissolves 2. nucleoli disappear 3. centrioles migrate to opp poles 4. spindle apparatus begins to form
Telophase I
1. nuclear membrane forms around each new nucleus (chormosome still consists of 2 sister chroatids joined at the centromere ) -cells are now haploid 2. once homologous chromosomes separate, only "n" chromosomes are found in each daughter cell (23 in humans) 3. cell divides into 2 daughter cells by cytokinesis -Could be short rest period--INTERKINESIS-- where chromosomes partially uncoil
What does HYPERglycemia do to the kidneys?
1. overwhelm the nephron's ability to reabsorb glucose 2 causes glucose in urine 3. glucose in urine causes excessive water excretion and an increase in urine volume commonly complain of -polydipsia (increased thirst) -polyuria (increased frequency of urine output)
What does a macrophage do when it is activated?
1. phagocytizes the invader through endocytosis 2. digests the invader using enzymes 3. presents little pieces of invader (mostly peptides) to other cells using a Major Histocompatability Complex (MHC) -binds to pathogenic peptide (antigen) -once the MHC binds to the antigen, the complex travels to the cell surface where it can be recognized by the cell of the adaptive immune system -release CYTOKINES (stims inflamm and recruits additional immune cells)
what are the two groups of mammals that birth their young differently?
1. prototherians (monotremes): duckbilled platypus, echina (spiny anteater) -they encase their developing embryos with hard-shelled amniotic eggs and lay then to be hatched -oviparty = method of development 2. metatherians (marsupials): koalas, kangaroos -metatherian fetus (joey) undergoes some dev in uterus and then blimbs out of birth canal and into her marsupium (pouch)
What occurs first in neurulation?
1. rod of MESOdermal cells (notochord) forms along the axis of the organism like a primitive spine (remnants of notochord persists in intervertebral discs between vertebrae)
What are the two major functions of the thyroid?
1. setting basal metabolic rate -mediates this by releasing Triiodothyronine (T3) and thyroxine (T4) 2. promoting Calcium homeostasis -releases Calcotonin
Why is the biconcave shape of the RBC important?
1. shape assists in traveling through capillaries 2. increases cell's surface area to increase gas exchange
What happens when a steroid hormone binds to a receptor?
1. steroid-hormone receptor complex undergoes CONFORMATIONAL changes (after steroid bound to complex) 2. receptor can bind directo to DNA -causes increased/decreased transcription of particular genes (depends on ID of hormone) Common conformational change = dimerization
what happens to allow for male sexual maturation at/during puberty?
1. testosterone production increases during puberty 2. sperm production begins during puberty 3. FSH stimulates ther Sertoli cells and striggers sperm maturation -LH causes interstitial cells to produce testosterone -Testosterone helps to develop and maintain male repro system and... -cause dev of Secondary Sexual Characteristics (facial/axillary hair, deep voice, increase muscle mass)
What are the 5 criteria of the Hardy-Weinberg equilibrium?
1. the population is very large (no genetic drift) 2. There are no mutations that affect the gene pool 3. mating between individuals in the population is random (no sexual selection) 4. there is no migration of individuals into or out of the population 5. the genes in the population are all equally successful at being reproduced
how do the nares/internal airways (last point) fight invaders?
1. vibrissae (hairs) 2. lysozyme (attacks peptidoglycan walls of gram pos bacteria) -also in saliva, tears 3. internal airways lined with mucous which traps particulate matter and large invaders -propels invaders up respiratory tract to be expelled or swallowed -MUCOCILIARY ESCALATOR
What are the 2 layers that oocytes are surrounded by?
1. zona pelluncida: surround the ooctye itself and is an acellular mixture of glyroproteins that protect oocyte and contain compounds necessary for SPERM BINDING 2. corona radiata: lies outside the zona pelluncida. Layer of cells that adhered to oocyte during Ovulation
What is the area of gas exchange in the lungs? (numeric figure)
100 m^2
What is the life-time of RBCs?
120 days -cells in liver and spleen phagocytize senescent (old) RBCs
What is a normal hemoglobin for males/females?
13.5 - 17.5 g/dL males 12.0-16.0 g/dL females
When do estrogen levels peak?
14 days 21 days
how much do our kidney's filter daily?
180 L = approx 36 x our blood volume -filter entire volume in 40 minutes
what are the genotypic and phenotypic ratios for crossing heterozygotes?
1:2:1 genotype 3:1 phenotye
Prophase
1st phase of mitosis 1. condensation of chromatin into chromosomes -centriole pairs (cylindrical organelles) separate and move toward opposite poles of cell. outside nucleus in CENTROSOME) -Responsible for CORRECT Division of DNA 2. centrioles migrate to opp poles of cell, begin to form SPINDLE FIBERS (microtubules) (Centrosome = 1 of 2 microtubule organizing centers of cell (otehr is basal body of flagella/cilia) 3. fibers radiate outward and attach to chromosomes (NM dissolves) 4. some microtubules form ASTERS tha anchor centrioles to NM 5. nucleoli become less distinct and may disappear completely 6. KINETOCHORES (appear at center of centrosome) are protein structures that serve as attachemnt points for specific fibers of the SPINDLE APPARATUS (Kinetochore fibers)
What is the umbilical cord made of?
2 arteries 1 vein encased in a gelatinous substance -vein carries freshly oxygenated blood rich with nutrients from PLACENTA to EMBRYO -Arteries carry deoxy blood and waste to placenta for exchang
disruptive selection
2 extreme phenotypes are selected over the norm -facilitated by POLYMORPHISMS: naturally occuring differences in form between members of same population (light and dark coloration in species)
What is the ploidy of the daughter cells produced from meiosis I and meiosis II?
2 haploid daughter cells from meiosis I 4 haploid daughter cells from meiosis II
what type of chains make up an antibody?
2 identical heavy chains and 2 identical light chains -held together by disulfide linkages and noncovalent interactions
When do progesterone levels peak?
21 days
How many homologous pairs of chromosomes do humans have?
23 homologous pairs of chromosomes (homologues) -each homologue contains 1 chromosome inherited from each parent (homologous pairs are considered separate chromosomes and sister chromatids are identical strands of DNA connected at centromere)
What is biological sex determined by?
23rd pair of chromosomes
What happens if the antibody is secreted into body fluids and is bound by an antigen ?
3 possibilities 1. once bound to a specific antigen, the antibodies may attract other leukocytes o phagocytize those antigens immediately (OPSONIZATION) 2. antibodies cause pathogens to Agglutinate, forming large insoluble complexes that can be phagocytized 3. antibodies can block the ability of a pathogen to invade tissues, essentially neutralizing it
What/where are the parathyroid glands?
4 small pea-sized structures that sit on the posterior surface of the thyroid
What is a normal hematocrit (measure of RBCS) for males/females?
41-53% males 36-46% females
What percentage of blood is liquid and cells
55% liquid 45% cells
Rate of SA node?
60-100 bpm w/o neuro input (causes both atria to contract simultaneously
How many and what type of products does the anterior pituitary gland secrete?
7 products 4 tropic 3direct FLAT PEG FSH LH ACTH TSH (all are peptide) Prolactin Endorphins Growth hormone (GH
What happens in the 3rd trimester?
7-8 month rapid growth, brain dev -Antibodies transported by highly selective active transport form the mother to fetus for protection against foreign agents -transfer begins early in pregnancy, but is highest in 9th month just before birth -as growth rate slows, fetus becomes less active and has less room to move
What are the pH the body usually tries to stay within?
7.35 -7.45
9+2 structure
9 pairs microtubules form outer ring and 2 microtubules i center form both cilia and flagella seen only in EUkaryotic cells bacterial flagella have diff structure
what is the normal range for BP?
90/60 to 120/80
what is the ratio for dihybrid crosses between 2 heterozygotes with complete dominance
9:3:3:1
missense mutation
A base-pair substitution that results in a codon that codes for a different amino acid.
Negative-pressure breathing
A breathing system in which air is pulled into the lungs when the lung volume is expanded.
Punnett Square
A chart that shows all the possible combinations of alleles that can result from a genetic cross
mutagens
A chemical or physical agent that interacts with DNA and causes a mutation.
dihybrid cross
A cross between individuals that have different alleles for the same gene
active immunity
A form of acquired immunity in which the body produces its own antibodies against disease-causing antigens. -immune system is stimulated to produce antibodies against a specific pathogen -generates B cells (memory)
Complement system
A group of about 30 blood proteins that may amplify the inflammatory response, enhance phagocytosis, or directly lyse extracellular pathogens. -in the blood -acts as a NONspecific defense against bacteria -punches holes in the CW of bacteria --> osmotically unstable -can NOT be modified to target a specific organism over others
esophagus
A muscular tube that connects the mouth to the stomach. -top 1/3 = skeletal muscle-somatic (voluntary) -middle = mix -bottom 1/3 = smooth muscle -autonomic/ involuntary
silent mutation
A mutation that changes a single nucleotide, but does not change the amino acid created. -most commonly in 3rd nucleotide place because there is a degeneracy (wobble) in genetic code
nonsense mutation
A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.
lysogenic cycle
A phage replication cycle in which the viral genome becomes incorporated into the bacterial host chromosome as a prophage/provirus and does not kill the host. -enviro factors (radiation, light, or chemicals) may cause the provirus to leave the genome and revert to the lytic cycle allows transduction of genes from one bacterium to another -infection with one phage makes bacterium less susceptible to superinfection (more than 1 virus)
Na+/K+ ATPase
A protein found in the plasma membrane of all cells in the body that uses the energy of an ATP (hydrolyzes ATP) to move three Na+ ions out of the cell and two K+ ions into the cell, thus establishing concentrations gradients for these ions across the cell membrane. -pumps ions back to their original positions -more ATP spent by Na/K ATPase to maintain gradients than for any other single purpose
What are the fat-sol vit?
A, D, E, KF
which zone or band does not change its length during muscle contraction?
A-band since it is the length of the entire myosin
what is reabsorbed at the proximal convoluted tubule?
AA glucose H2O water-sol vitamins majority of salts almost 70% of filtered Na will be reabsorbed here , filtrate remains isotonic to the interstitium site of secretion (into tubule for urine)of H+, K+, ammonia, and urea
What are the two major families of anitgens?
ABO antigens Rh factor
Inhalation
ACTIVE process -use diaphragm and external intercostal muscles -intrathoracic volume increases -increase in Intrapleural volume leads to a DECREASE in intrapleural pressure
Which 3 hormones are primarily involved in water homeostasis?
ADH -increases blood volume and decreases blood osmolarity Aldosterone -increases blood volume with no effect on osmolarity Atrial Natriuretic peptide (ANP) -decreases blood volume with NO effect on osmolarity
how does ADH affect blood osmolarity?
ADH governs water reabsorption which results in lower blood osmolarity
list some of the enzymes that are involved in feeding behavior
ADH/vasopressin (trigger thirst) aldosterone glucagon (stims hunger) ghrelin (stims hunger) leptin (stims satiety) cholecystokinin (stims satiety)
What is possible with each step of the signaling cascade?
AMPLIFICATION Ex: one hormone molecule may bind to multiple receptors before it is degraded -each receptor may activate multiple enzymes -this can trigger production of large quantities of second messengers -So each step can result in an INCREASE in Signal intensity
What is a key diff between ANS and SNS?
ANS contains 2 neurons SNS motor neuron goes directly from spinal cord to muscle WITHOUT synapsing
what does the binding of ATP to the myosin head do?
ATP binding allows the myosin filament to disconnect from actin
if Corticotropin-Releasing Factor (CRF) is released from the hypothalamus, what does the ANTERIOR pituitary release?
Adrenocorticotropic Hormone (ACTH) -causes increase in level of cortisol in blood -excess cortisol bad, so cortisol inhibs hypothalamus and anterior pituitary from releasing CRF and ACTH respectively -Cortisol receptors must be present in these organs -acts on ADRENAL COTREX
Sensory neurons
Afferent -transmit sensory information from sensory receptors to spinal cord and Brain -bring info from periphery, end dorsally (from back side of spinal cord) -Cell bodies in dorsal root ganglia
genetic map
An ordered list of genetic loci (genes or other genetic markers) along a chromosome. -represents the relative distance between genes on a chromosome 1 map unit or 1 centimorgan = 1% change of recombination occurring between 2 genes
Monocytes
An agranular leukocyte that is able to migrate into tissues and transform into a macrophage. -become macrophages in tissues -many tissues have resident populations of macrophages with specific names -microglia (CNS) -langerhans cells (skin) -cell-meiated immunity (driven by T-cells)
Nondisjunction
An error in meiosis or mitosis in which members of a pair of homologous chromosomes or a pair of sister chromatids fail to separate properly from each other. -results in zygotes having too many or too few copies of that chromosome -trisomy 21 (down syndrome), klinefelter and turner syndrome -Turner Syndrome 45X (female)
genotype
An organism's genetic makeup, or allele combinations.
What are the Cortical Sex Hormones?
Androgens and Estrogens
equational division
Another name for meiosis II because cells in meiosis II have the same number of chromosomes at the beginning and at the end of the process. -separation of sister chromatids without a change in poloidy (similar to MITOSIS)
What is the valve that separates the L ventricle from the aorta?
Aortic valve
What hormones/structure controls the ovaries?
Anterior Pituitary Gland Gland secretes FSH and LH ovaries produce estrogens and progesterone
dendritic cell
Antigen-presenting cells that process antigen material and present it to T-cells -presents portions from pathogens or cancer cells
what are the surface proteins that RBCs express?
Antigens -any spcific target (usually protein) to which the immune system can react
What are the 3 domains of life?
Archaea, Bacteria, Eukarya
What does the heart release in order to regulate salt and water balance?
Atrial Natriuretic Peptide (ANP) -cells in atria stretched from excess blood volume, release ANP -Promotes excretion of Na which increases Urine Volume -Antagonistic to aldosterone because it lower blood volume and pressure (NO effect on osmolarity)
Which way do axons carry neural signals?
Axons carry neural signals AWAY from the soma Dendrites carry signals toward the soma (Dendrites receive incoming messages)
what do B-cells turn into?
B-cells turn into plasma cells and produce antibodies as part of the adaptive immunity
What happens after the MORULA is formed?
BLASTULATION -forms the BLastula (mammaliam blastula = blastocyst) Blastula: hollow ball of cells with a fluid-filled inner cavity known as the BLASTOCOEL
What activates neutrophils?
Bacteria (especially those that have been opsonized (tagged with an antibody on their surface)
What is the valve between the left atrium and left ventricle?
Bicuspid valve(mitral)
arteries
Blood vessels that carry blood away from the heart toward pripheral tissues
Where does lymphocyte maturation occur?
Bone barrow: B-cells -responsible for antibody generation Thymus: T-cells -kill virally infected cells and activate other immune cells
what hormone promotes bone formation?
CALCITONIN -released by parafollicular cells of THYROID in response to HIGH Ca lowers blood Ca
what receptor do retroviruses bind to?
CCR5
Helper T cells
CD4+ T -cells coordinate the immune response by secreting chemicals known as LYMPHOKINES lymphokines can recruit other immune cells (plasma cells, cytotoxic T-cells, and macrophages) and INCREASE their activity
What do the trophobalstic cells give rise to?
CHORION -an extraembryonic membrane that devs into PLACENTA Trophoblastic cells also form CHORIONIC VILLI (microscopic fingerlike projections that penetrate the endometrium) -forms an outer membrane around the amnion (additional protection)
What happens after the sperm penetrates the CM?
CORTICAL REACTION -release of Ca ions -Ca ions depolarize membrane of ovum
What happens when the AP reaches the sarcoplamic reticulum?
Ca2+ is released Calcium ions bind to a regulatory subunit in troponin, triggering a change in the conformation of tropomyosin (which troponin is bound to)
Pancreatic lipase
Capable of breaking down fats into free fatty acids and glycerol
What class of molecules are Epi and norepi in?
Catecholamines Epi/NE: AA derivative hormones
chemotaxis
Cell movement that occurs in response to chemical stimulus
Stem cells
Cells that have not yet differentiated or give rise to OTHER cells (embryonic and adult) and may become one of many different tissue types.
What enzyme is released in response to the entry of chyme (AA, and fat) into the duodenum?
Cholecystokinin (CCK) peptide hormone -stims the release of both BILE and PANCREATIC JUICES and acts on brain to promote SATIETY -released in response to the entry of chyme (AA, and fat) into the duodenum
Prophase I Pachytene
Chromatids may break at the poi-single crossovers -double crossoversnt of contact, CHIASMA (CHIASMATA) and exchange equivalent piences of DNA (CROSSING OVER) -crossing over occurs between homologous chromosomes, not sister chromosomes (identical) -RECOMBinATION can unlink linked genes which increases genetic variety (increases genetic combinations that can be produced via gametogenesis
Metaphase II
Chromosomes line up at the equator (metaphase plate)
after the DCT, where does filtrate go?
Collecting duct -final conc of urine depends largely on permeability of collecting duct -responsive to both aldosterone and ADH -as permeability of collecting duct increases, so does water reabsorption (further concentrates urine) -if body well hydrated, collecting duct will e fairly impermeable to salt and water -if conserving H2O, then ADH and aldosterone increase H2O absorption in collecting duct = more concentrated urine
What is a signaling cascade?
Connection between the hormone at the surface and the effect brought about by second messengers within the cell
How does the hypothalamus control the pituitary?
Controls the anterior pituitary via paracrine release of tropic hormones into portal system Controls the posterior pituitary via neurohypophysis - direct nerve stimulation hypothalamus can have organism wide effects -some parts regulate blood osmolarity, others appetite and satiety
what are the divisions of the kidney?
Cortex and medulla
what are the two supplemental energy reserves in muscle?
Creatine phosphate myoglobin
What do ENDORPHINS do?
DECREASE the perception of pain -an induce sense of euphoria -morphine mimics the effect of these
what muscles are involved in breathing?
DIAPHRAGM chest wall, back, neck
What does Calcitonin do?
Decreases plasma calcium conc (in 3 ways) 1. increasing Ca excretion from KIDNEYS 2. decreasing Ca absorption from gut 3. increasing STORAGE of Ca in the Bone
What comes after cell specification?
Determination -commitment of a cell to a particular function in the future -IRREVERSIBLY comits a cell to a specific lineage
alleles
Different forms of a gene
What occurs after determination?
Differentiation: purpose is for cell to produce what it needs to carry out function -dev into determined cell via changes in structure, function, biochem to match cell type -
What is dimerization of a steroid-hormone?
Dimerization is a common form of conformational change where there is a pairing of 2 receptor-hormone complexes
What are the major waste products excreted in the urine?
Dump the HUNK H+ Urea NH3 K+
What cellular layer is the Adrenal MEDULLA derived from?
ECTOderm
What germ layer is the nervous system derived from?
ECTOderm
what lines bloodvessels and what is the advantage of them?
ENDOthelial cells help to maintain the vessel by releasing chemicals that aid in vasodilation and vasoconstriciton -can allow WBCs to pass through -when damaged, release chemicals that are involved in the formation of blood clots
motor neurons
Efferent -transmit motor information from the brain and spinal cord to muscles and glands -exit spinal cord ventrally
What hormones are secreted from the adrenal Medulla?
Epi/NE AA derivative
cellular portion of blood composed of?
Erythrocytes leukocytes platelets (all blood is formed from hematopoietic stem cells which originate in bone marrow)
What hormone can have both a POS and NEG feedback loop?
Estrogen
How is PTH regulated /
FEEDBACK INHIB - levels of plasma calcium rise, PTH secretion decreses
What type of messenger is a peptide hormone?
FIRST messenger: binds to receptor and triggers transmission of Second signal (SECOND messenger)
if Gonadotropin releasing hormone (GnRH) is released from the hypothalamus, what does the ANTERIOR pituitary release?
FSH and LH -these act on the gonads (testes and ovaries)
F generation
Filial generation, offspring
What types of cells are found in thyroid tissue?
Follicular cells (produce Thyroid HORMONES) C-cells (Parafollicular cells) produce CALCITONIN
directional selection
Form of natural selection in which the entire curve moves; occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve -Ex: resistant bacteria
What are the 4 stages of actively dividing cells?
G1 S G2 M
What is a collection of cell bodies in the PNS called?
Ganglion
What happens after implantation?
Gastrulation -the generation the 3 distinct cell layers (formation of gastrula from blastocoel) gastrula: the embryonic stage characterized by the presence of (1) Ectoderm, (2) mesoderm, (3) endoderm
What does the axon hillock do?
Generates and transmits the electrical impulse down the axon to the effector or next nerve AKA trigger zone -sums excitatory and inhibitory signals.If excitatory enough, triggers action potential
pyloric glands
Glands located in the walls of the stomach that secrete the hormone GASTRIN (peptide hormone) in response to certain substances in food. -G-CELLS secrete gastrin
if Growth Hormone-releasing Hormone (GHRH) is released from the hypothalamus, what does the ANTERIOR pituitary release?
Growth Hormone (GH)
what muscular bans/zones decrease in length with contraction?
H-zone gets SMALLER I-band gets SMALLER distance between Z-lines and distance between M-lines become SMALLER
What cleaves pepsinogen to pepsin?
HCl
cardiac output
HR x SV total blood pumped by a ventricle in a minute about 5 L per minute
compact bone
Hard, dense bone tissue that is beneath the outer membrane of a bone
What are the major types of T-cells?
Helper T-cells suppressor T-cells Killer (cytotoxic) T-cells memory T-cells
What does gastrin do?
Induces the PARIETAL cells in the stomach to secrete more HCl and signals the stomach to contract, mixing its contents
peristalsis
Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system. -move food to stomach
What are the 2 MOST important ions in maintaining resting membrane potential?
K+ and Na+ -K+ conc inside cell avg 140 mM (outside cell = 4mM) -Transmembrane Potassium Leak Channels allow K+ to Continually leak out making outside cell slightly POS charged and inside cell slightly NEG charged -However, reaches point of ---Equilibrium potential of Postassium---
What secretes Erythropoietin?
Kidneys Erythropoietin: stims bone marrow in increase production of RBCs -secreted in response to low O levels in blood
What do cytotoxic T cells do?
Kill abnormal and foreign cells if VIRALLY infected
What 2 organs in the fetus don't serve major functions prior to birth?
Liver an Lungs -oxygen = placenta -detoxification of blood = mother's liver -lack of use = underdevelopment of lungs and liver and sensitivity to High BP. - protects via SHUNTS
locus
Location of a gene on a chromosome
What class of MHC presents foreign material to CD4+ cells and what do those cells fight best against?
MCH II exogenous antigens so...bacterial, fungal, parasitic infections
sensory receptors in dermis
MERKEL cells (discs) - receprots present at epidermal-dermal junction -connected to sensory neurons and responsible for DEEP pressure and TEXTURE sensation within skin FREE NERVE ENDINGS -respond to pain MEISSNER's corpuscles -respond to LIGHT touch RUFFINI endings -respond to stretch PACINIAN corpuscles -respond to DEEP pressure and VIBRATION
What cellular layer is the adrenal CORTEX derived from?
MESOderm
What class of MHC do cytotoxic T cells need to recognize viral antigens? What are CTLs most effective against?
MHC I Endogenous antigens more effective against viral (and intracellular bacterial or fungal) infections
what class of MHC do ALL Nucleated cells in the body display?
MHC class I -any protein produced within a cell can be loaded onto MHC-I and presented on the surface of the cell -monitor health of cell, infected cell would present nonself proteins -ENDOGENOUS pathway --if invaded, killed by Cytotoxic T-lymphocytes to prevent infection of other cells
are alleles far away more of less likely to be separated in the event of a cross-over?
MORE likely
What does the embryo become after several divisions?
MORULA: solid mass of cells
Where are ADH and Oxytocin made and stored?
Made: Hypothalamus Stored: Neurohypophysis (posterior pituitary)
When is Meiosis II triggered in females?
Meiosis II is triggered when a sperm cell penetrates the corona radiata and zonapellucida (sperm does this with the help of acrosomal enzymes) -the second meiotic division is to split a mature ovum and another polar body (broken down)
In classical genetics, what law does crossing over explain?
Mendel's second law (of independent assortment) -the inheritance of one allele has no effect on the liklihood of inheriting certain alleles for other genes
What stage of development is the egg cell in at ovulation?/
Metaphase II
List some differences between Mitosis and Meiosis
Mitosis 1. 1 round of replication and 1 round division Meiosis 1. 1 round replication, 2 rounds division 2. Meiosis 1 has reductional division, (generates haploid daughter cells) Meiosis II (similar to mitosis) has equational division, separation of sister chromatids without change in ploidy -Chrmosome number is halved in Meiosis I, daughter cells have haploid number of chromosomes.
how is the release of hormones in the hypothalamus regulated?
NEGATIVE feedback: when a hormone (or product) later in the pathway inhibit hormones (or enzymes) earlier in the pathway -maintains homeostasis -conserves energy by restricting production of substances already present in sufficient quantities
Are peptide hormones charged?
NO -so CANNOT pass through plasma membrane -MUST bind to EXTRAcellular Receptor
What type of cell can recognize the virus caused downregulation of MHCs and what happens?
Natural Killer cells (NK) -nonspecific lymphocyte can detect downregulation of MHC and induce APOPTOSIS in the virally infected cells so they destroy body's own cells that have become infected (cancer cells can also down regulate)
what is the descending limb of the loop of henle permeable to?
ONLY to water has increasing osmolarity as it descends -can change osmolarity to conserve or get rid of water
what type of chemical/energy system are biological systems considered?
OPEN systems because they exchange both energy and matter with the environment -when biochem studies done on cellular or subcellular level, systems considered CLOSED because no exchange of matter with environment
What does the umbilical vein carry?
OXYgenated blood from the Placenta to the Fetus
What happens once the 3 germ layers have been formed?
Neurulation--dev of nervous system
myoglobin
O carrier that uses Fe and heme group to bind O
Negative selection of T cells
Occurs in medulla of thymus. T cells expressing TCRs with high affinity for self antigens undergo apoptosis. -self-reactive cells --> apoptosis
What type of feedback loop does oxytocin use?
POSITIVE -release promotes uterine contraction, promotes more release = stronger contraction ect... end point = delivery
What hormone does not require something to be released for the hypothalamus?
PROLACTIN -Prolactin Inhibiting Factor (PIF) (dopamine) is released by hypothalamus and decreases/inhibs prolactin from being secreted -ONLY in ABSCENCE of PIF can prolactin be secreted
What is the end point of the coagulation cascade?
PRothrombin ---> thrombin Enzyme: thromboplastin this allows Fibrinogen to convert into FIBRIN (forms small fibers that aggregate and cros-link into a woven structure that capture RBCs and platelets to form a stable clot over the area
What hormone do the parathyroid glands secrete and what does it do?
Parathyroid Hormone (PTH) -serves as an antagonist hormone to Calcitonin -RAISES blood Calcium levels 1. decreases excretion of Ca by the KIDNEYS 2. increases absorption of Ca in the gut (via Vit D) 3. increases bone reabsorption, frees up Ca
p generation
Parental generation, the first two individuals that mate in a genetic cross
punctuated equilibrium
Pattern of evolution in which long stable periods are interrupted by brief periods of more rapid change
What are the special receptors found on macrophaces and dendritic cells?
Pattern recognition receptors (PRR) -Toll-like Receptors (TLR) -allow for the production of appropriate cytokines to recruit the right type of immune cells -each immune cell has different weapons that can target particular groups of pathogens
What type of hormone signaling activates the G Protein-coupled receptor?
Peptide Hormone 1. peptide hormone binds 2. triggers receptor to activate or inhib enzyme of Adenylate Cyclase 3. this raises/lowers levels of cAMP 4. cAMP can bind to INTRAcellular targets (Ex: ***Protein Kinase A) 5. Protein Kinase A phosphorylates transcription factors like cAMP Response Element-Binding Protein (CREB) -CREB exerts hormone's full effect -Protein Kinase A can modify other enzymes/transcription factors ---> have rapid or slow effect on cell
What do the neural crest cells become?
Peripheral nervous system --sensory ganglia, autonomic ganglia, adrenal medulla, schwann cells -specific cell types in other tissues: Calcitonin-producing cells of THYROID, Melanocytes in skin) -Then ECTOdermal cells will migrate over neural tube and crest to cover rudimentary nervous system
What type of selection do T-cells undergo?
Positive selection Negative selection
synopsis of mitosis
Prophase: chromosomes condense, spindle forms metaphase: Chromosomes Align Anaphase: sister chromatids separate Telophase: new nuclear membrane forms
Erythrocyte
RBC biconcave -each contains 250million molec of hemoglobin. each heme group can bind 4 molec of O2, So ,each RBC can carry approx 1 bill molec of O2
besides aldosterone, what does decreased BP stimulate the release of?
RENIN form juxtaglomerular cells in kidney -renin cleaves angiotensinogen (liver protein) to form angiotensin I -angiotensinI metabolizeed by angiotensin-converting enzyme in lungs to form Angiotensin II (promotes release of adlosterone from renal cortex)
Saltatory conduction
Rapid transmission of a nerve impulse along an axon, resulting from the action potential jumping from one node of Ranvier to another, skipping the myelin-sheathed regions of membrane.
What is aldosterone primarily controlled by?
Renin-angiotensin-aldosterone system
Germ cells
Reproductive cells that give rise to sperm and ovum -daughter cells not equivalent (as they are in autosomal cell division) HAPLOID (n)
What is a cell that is induced called?
Responder (responsive cell) -must be COMPETENT, or able to respond to signal
what effect does increased CO2 have on the oxyhemoglobin dissociation curve?
Right shift in bicarb buffer equation resulting in increased H+ (decreased pH) -These protons can bind to hemoglobin causing a decrease in the affinity of hemoglobin "Bohr Effect" (increased PCO2, [H+], decreased pH) all signs of high O demand, high rate of cellular metabolism, accumulation of lactic acid **decreased affinity allows more O to be released in the tissues
Which lung is bigger?
Right, has 3 lobes left as 2 lobes and has a small indentation due to the heart
What is the last point in the meiotic cycle in which the cell has diploid number of chromosomes?
Telophase I
list the nodes of electric conduction in the heart in order of occurance
SA node AV node Bundle of His (AV bundle) Purkinje fibers
what is the initial stage of cell specialization?
SPECIFICATION -cell reversibly designated as a specific cell type before determination, cell can become ANY cell type
what is the notable gene on the Y chromosome?
SRY (Sex-determining region Y) -this region codes for transcription factor that initiates testis differentiation and (therefore) formation of male gonads. -in absence of Y chromosome, all zygotes FEMALE -in presence of Y chromosome, all zygotes MALE
How do cells with same genes dev into diff cell types with specialized functions?
Selective Transcription -only the genes needed for that particular cell type are transcribed -related to concept of INDUCTION (ability of one group of cells to influence the fate of nearby cells. process mediated by chem sub (INDUCERS) which diffuse from Organizing Cells tot he Responsive cells) -these chemicals responsible for processes like guidance or neuronal axons -induction ensures the proximity of different cell types that work together in an organ
where does myogenic activity begin and end?
Sinoatrial node (SA) Atrioventricular node (AV) bundle of His Purkinje fibers
what inhibits both insulin and glucagon secretion?
Somatostatin -high blood-glucose and AA concentrations stimulate its secretion, some gastrointestinal hormones -produced by the hypothalamus, where it decreases GH secretion also. Always INHIBITORY
interphase of cell cycle
Stages G1, S, G2 -longest part of cell cycle -actively dividing cells spend about 90% of their time in this phase
glial cells (neuroglia)
Support cells in nervous tissue, do not convey electrical signals, are capable of cell division. -astrocytes -ependymal cells -microglia -oligodendrocytes and Schwann cells
What circuits are used if nervous input from the brain or brainstem is required?
Supraspinal circuits
what returns most of the lymphatic fluid to the central circulatory system
THROACIC DUCT
What are the pathogens than can cross the placenta?
TORCHES TOxoplasma gondii Rubella Cytomegalovirus HErpes or HIV Syphilis
Cervix
The opening to the uterus -connects to vaginal canal (where sperm are deposited during intercourse)
frequency summation
The process by which many successive neural impulses stimulate a neuron or a muscle until the cell being stimulated experiences an action potential or a contraction. contractions combine, become stronger, more prolonged
hypermutation
The process each B-cell's antigen-bind region undergoes to find the best match for antigen -only those that can bind to the antigen with high affinity survive -provides mechanism for generating specificity called CLONAL SELECTION
reciprocal development
The process where structures developed from the induction of other structures cause the development of the inducing structure into a new structure. i..e. the optic vesicle induces part of ectoderm to form lens placode. Lens placode induces optic vesicle to create optic cup. Optic cup induces lens placode to become cornea and lens.
diluting segment
Thicker portion of the ascending loop of Henle with larger cells due to more mitochondria in these cells to facilitate active transport. These cells are pushing out salts against their concentration gradient, since the fluid inside the loop of Henle has become hypotonic compared to the interstitium. This is the only portion of the nephron that can produce urine more dilute than blood. -important during times of overhydration, can elim excess water
Axes
Three organ systems to describe feedback control: hypothalamic-pituitary-adrenal axis, hypothalamic-pituitary-ovarian axis, etc
What facilitates the maturation of T-cells?
Thymosin -peptide hormone secreted by Thymic cells
if Thyroid-Releasing Hormone (TRH) is released from the hypothalamus, what does the ANTERIOR pituitary release?
Thyroid-Stimulating Hormone -acts on Thyroid
What is the valve between the right atrium and right ventricle?
Tricuspid
Schwann cells
Type of glia in the PNS, Supporting cells of the peripheral nervous system responsible for the formation of myelin.
Oligodendrocytes
Type of glial cell in the CNS that wrap axons in a myelin sheath.
what is the equation for vital capacity?
VC = IRV + ERV + TV
virons
Viral progeny produced after stealing host cell machinery, replicating, and lysing
What does PTH activate?
Vitamin D -which is required for absorption of Ca and phosphate in gut
What happens once neuron is at threshold?
Voltage-gates Na channels open -respond to depolarization and allow sodium ions to flow through -ELECTROCHEMICAL Gradient promotes Na into cell (NEG inside cell, high [Na] outside as well) -RAPID DEPOLARIZATION
Leukocytes
WBC -less than 1% total blood volume so about 4500-11000 WBCs / microliter of blood agranulocytes and Granulocytes
What chromosome, if mutated, leads to sex-linked disorders?
X chromosome because it contains so much info "X-linked" disorders
What are the different lines, zones, and bands of the sarcomere?
Z-lines M-line I-band H-zone A-band
list the stages of dev from zygote to gastrula
Zygote--> 2-, 4-, 8-, and 16- cell embryo ---> omrula--> blastula (blastocyst-->gastrula
Inducers
a chemical substance passed from an organizing cell to a responsive cell, resulting in differentiation of the responsive cell -often GROWTH FACTORS (peptides tha tpromote differentiation and Mitosis in certain tissues) -Growth factors usually act on specific cell types/areas (determined by competence of cell) -so growth factors can sort of code for a specific tissue
pancreatic juices
a complex mixture of several enzymes in a BICARBONATE-rich alkaline solution -bicarb helps neutralize HCl --provide ideal working enviro for digestive enzymes (most active around pH 8.5)
periostium
a dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints. serves as site for muscle attachemnt
penetrance
a population measure defined as the proportion of individuals in the population carrying the allele who actually express the phenotype ex: huntingtin gene. Individuals with more than 40 sequence repeats have FULL PENETRANCE--100% of individuals with this allele show symptons of Huntingtons disease individuals with fewer sequence repeats show HIGH PENETRANCE (most , but not all, of those with the allele show symptoms of the disease with reduced sequence repeats you have reduced penetrance, low penetrance, or nonpenetrance
complete dominance
a relationship in which one allele is completely dominant over another
ER
a series of interconnected membranes that are actually contiguous with the nuclear envelope -double membrane folded into numerous invaginations, creating complex structures with a central lumen
hemizygous
a situation in which only one allele is present for a given gene (as is the case for parts of the X chromosome in males)
tetanus
a sustained muscular contraction resulting from a rapid series of nerve impulses no relaxation period
lytic cycle
a viral reproductive cycle in which copies of a virus are made within a host cell, which then bursts open, releasing new viruses
How long does human gestation last?
about 280 days
how is the signal at the NMJ terminated?
acetylcholinesterase is degraded in the synapse which allows the sarcolemma to repolarize as signal decays, Ca release ceases, SR takes up Ca form sarcoplasm
how does the stomach eliminate most of the pathogens that reach it?
acid
chyme
acidic, semifluid mixture resulting from digestion of solid food in stomach
What do helper T cells do?
activate B lymphocytes -coordinate the immune system through lympokines and respond to antigen bound to MHC-II
What activates NK cells?
activated by cells that do NOT present MHC
gastric glands
activated by signals from the vagus nerve of the parasympathetic nervous system respond to signals from brain, activated by sight, taste, and smell 3 types of cells: 1. mucous (produce bicarbonate-rich mucous to protect muscular wall from acid), 2. chief (secrete PEPSINOGEN (zymogen form of pepsin--proteolytic enzyme) 3. parietal cells (Secrete Hydrogen ions as HYDROCHLORIC ACID)
Spatial summation (AP)
additive effects base on # and location of incoming signals Ex: large # INHIB signals firing directly on soma cause more profound HYPERPOLARIZATION of axon hillock than depolarization from few excitatory signals firing on dendrites
summation (AP)
additive effects of multiple signals Two types 1. temporal summation 2. spatial summation
bacteria can't use O, but not hurt by O
aerotolerant anaerobes are unable to use O for metabolism but are not harmed by its presence
restriction point
after G1 before S governs passage into S certain criteria (containing proper complement of DNA...ect) must be met for cell to pass this point -if cell fails, then cell cycle goes into arrest until DNA has been repaired. Main protein in control of this is p53
when is the block on lactation removed?
after expulsion of the placenta (before this milk ducts preped for lac) estrogen, progesterone, and dopamine levels decrease -milk ejection occurs after latching (nipple stim activates hypothalamus causing 1. contraction of smooth muscle to eject milk 2. hypothalamus stops releasing dopamine which allows release of prolactin (production and regulation of milk supply)
What are the plasma proteins and what are their functions?
albumin: osmotic balance, pH buffering fibrinogen: clotting immunoglobulins: defense (antibodies)
How do alcohol and caffeine affect ADH
alcohol and caffeine both inhibit ADH release and lead to the frequent excretion of DILUTE urine
what do the DCT respond to?
aldosterone (promotes Na reabsorption) -water will follow Na, concentrating the urine and decreasing its volune -also site of wast product secretion
how does Aldosterone affect blood osmolarity?
aldosterone causes both salt and water reabsorption and does NOT change blood osmolarity
how does aldosterone affect the DCT?
aldosterone works by altering the ability of the DCT and collecting duct to reasorb Na -aldosterone also increases K+ and H+ excretion
gene pool
all of the alleles that exist within a species
what type of response do muscle cells exhibit?
all-or-nothing -must reach threshold value nerves control overall force by the number of motor units they recruit to respond maximal response = all fibers within muscle are stimulated to contract simultaneously
what activates basophils and mast cells?
allergens
Why are valves in the heart necessary
allow heart to build up pressure and prevents backflow
what is the function of nuclear pores?
allow selective 2 way exchange of material between the cytoplasm and the nucleus
function of cytosol
allows diffusion of molecules throughout the cell, suspends organelles
retroviruses
an RNA virus that contains an enzyme REVERSE TRANSCRIPTASE, which transcribes RNA into DNA
What causes HYPERthyroidism?
an excess of the thyroid hormone which may result from a tumor or thyroid over-stim
where do cells that do not divide spend their time?
an off shoot of G1, G0 stage (G zero) -during this stage, the cell is living and carrying out its functions, without any preparation for division
bacteria don't require oxygen, can use fermentation
anaerobes
What are lymphocytes responsible for?
antibody production, immune system modulation, targeted killing of infected cells
What structure do arteries branch into?
arterioles and then to capillaries
What is the ascending limb of loop of henle permeable to?
ascending limb of loop of henle is ONLY permeable to SALTS and is impermeable to water -maximizes slat reabsorption due to decreasing medullary osmolarity
colon
ascending, transverse, desending, sigmoid -absorb H2O and salts (NaCl) from undigested material left over from small intestine -Small intestine absorbs more H2O than LI, so LI mainly concentrates remaining material to form FECES
conjugation
asexual repro -conjugation bridge (sex pili) -sex pili there because bacterium contains sex factors (such as fertility (F)) -transfer of genetic material is unidirectional from male (+) to recipient female (-) -can transfer copies of F to other bacterium. -rapid acquisitio of antibiotic resistance or virulence factors throughout colony
What is triggered at the start of puberty?
at the start of puberty, the hypothalamus tops restricting Gonadotropin-Releasing Hormone which triggers the ANTERIOR Pituitary Gland to synthesize and release... Follicle-Stimulating Hormone (FSH) and... Lutenizing hormone (LH)
where do fat -sol vit dissolve inot in digestion?
at-sol vit dissolve directly into chylomicrons to enter the lymphatic circulation -failure to digest and aborb fat property causes pathologies in liver, gallbladder, pancreas, or small intestine--may lead to deficiencies in fat-sol vitamins
Artial kick and volume
atrial systole to increase filling of ventricles 5-30% of cardiac output
what separates the atria from the ventricles?
atrioventricular valves
What ways can cell-cell communication occur?
autocrine paracrine juxtacrine ednocrine
what cells have 2 copies of each chromosome?
autosomal cells in animals are DIPLOID (2n)
What does white matter consist of?
axons encased in myelin sheaths -deeper than grey matter
What vasculature allows hormones to end up at target tissues?
capillaries (allows endocrine signals)
30% of dry matter in stool consists of...
bacteria -mainly anaerobes (cecum has many aerobic bacteria)
What are the 5 types of infectious pathogens?
bacteria, viruses, fungi, parasites, prions
what senses that BP is too high?
baroreceptors
bile
bile is a complex fluid composed of bile salts, pigments, and cholesterol
what is the major pigement in bile?
bilirubin -byproduct of the breakdown of hemoglobin -travels to liver where it is conjugated (attached to a protein) and secreted into bile for excretion -if unable to excrete, JAUNDICE occurs
what branches into veins?
capillaries --> venules--> veins
When does implantation occur?
blastula
why do local anesthetics work?
bloc voltage-gated Na+ channels - work well on SENSORY -Bec these neurons have small axonal diameters with little/no myelin (easy access) -Tetrodotoxin (TXTX) blocks Na+ voltage-gates channels. PUFFER fish. Phrenic nerves innervating diaphragm can't depolarize so no respiration
hematopoiesis
blood cell and platelet formation
hypophyseal portal system
blood leaving capillary beds in hypothalamus travels to a capillary bed in anterior pituitary to allow for paracrine secretion of releasing hormones
hepatic portal system
blood leaving capillary beds in the walls of the gut passes through the hepatic portal vein before reaching the capillary beds in the liver -AA enter circulation via hepatic portal system
renal portal system
blood leaving the glomerulus travel through an efferent arteriole before surrounding the nephron in a capillary network called vasa recta
what do the bone cannals contain?
blood vessels, nerve fibers, lymph vessels that maintain the health of the bone
peptidases
breakdown proteins into AA
what produces leukocytes?
bone marrow
where does the strength of compact bone come from?
bone matrix has both organic and inorganic components organic; collagen, glycoproteins, other peptides inorganic: Ca, phosphate, Hydroxide ions with harden together to form hydroxyaptitie crystals minerals (Na. Mg, K) also stored in bone
immovable joines
bonees that are fused toether to form SUTURES or similar frbrous joints anchor bones of skull toether
appendicular skeleton
bones of limbs, pectoral girdle, pelvis
cup around glomerulus
bowman's capsule
CNS composed of?
brain and spinal cord
lung structures
bronchioles to aleoli
if ureter was obstructed by a kidney stone, what would happen to flow in bowman's capsule?
build up or urine behind stone and cause distnetion of renal pelvis and nephrons -filtration wouldn't happen because there would be excessive pressure opposing movement of fluid in nephron
how are T3 and T4 produced?
by the iodination of tyrosine in the FOLLICULAR cells of the thyroid can 1. resent basal metabolic rate of body by making energy produciton more or less efficient, and altering utilization of glucose and FA
spongy bone
cancellous bone lattice strucutre of spongy bone is visible udner microscopy and consists of body spicules = trabeculae
what nutrients can pancreatic juices digest?
carbs, fats, proteins
Who do umbilical arteries carry?
carry DEoxygenated blood away from the fetus TO the Placenta
what does depolarization in the sarcolemma cause?
causes AP to spread down sarcolemma to the T-tubules inot ht emuscle tissues to the sarcoplasmic reticulum
What happens when an antigen binds to antibodies on the surface of a mast cell?
causes degranulation (exocytosis of granule contents) releasing histamine and causing an inflammatory allergic response
3 parts of large intestine
cecum, colon, rectum
what cycle do eukaryotic cells replicate through?
cell cycle
Since cells are not always in right area to carry out function, what steps can occur to change this?
cell migration cell death regeneration
Name the 4 regions of the spinal cord
cervical thoracic lumbar sacral
mutation
change in DNA sequence, and it results in a mutant allele (contrasted by wild-type = normal alleles)
genetic drift
changes in the composition of the gene pool due to change -tends to be more pronounced in small populations Ex: founder effect
list of digestive enzymes
check page 316
What senses if blood osmolarity is too high and what happens?
chemoreceptors sense if blood osmolarity is too high -indication of Dehydration -causes release of ADH (vasopressin) (peptide, made in hypothala., secreted from post pituitary) (increases REabsorption of water)
What are bile salts derived from?
cholesterol -NOT enzymes and do NOT directly perform chemical digestion -facilitate the mechanical digestion of fats and facilitate the chemical digestion of lipids
what type of neurons innervate sweat glands?
cholinergic (not andrenergic) -secrete acetylcholine) -ALL preganglionic neurons in autonomic nervous system and POSTganglionic neurons in parasympathetic system are cholinergic as well
What are genes organized into?
chromosomes
what are all genes (and noncoding DNA) organized into?
chromosomes
Prophase I: Diakinesis
chromosomes become fully condensed and nuclear membrane disentegrates prior to metaphase I
What catches material in the bronchi and trachea that has made it past the mucous membranes of the nose and mouth?
ciliated epithelial cells
Steroid hormone
class of hormones that can pass through the cell membrane; can be stored in the body -derived from cholesterol -derived from non-polar molec, so easily cross cell membrane -produced primarily by gonads and adrenal cortex -receptors usually INTRAcellular (in cytosol) or intranuclear (in nucleus)
What is the recombo frequency of tightly linked genes?
close to 0%
What is the recombo frequency of weakly linked genes?
close to 50%
What are clots composed of?
coagulation factors (proteins) and platelets, prevent/minimize blood loss
articular cartilage
coats the articular surfaces of the bones so that the impact is restricted to the lubricated joint cartilage
3 shapes of bacteria
coccus bacilli spirilli (treponema pallidum, borrelia burgdorferi, leptospira interrogans)
innate immunity
composed of defenses that are ALWAYS active against infection, but lack the ability to target specific invaders "nonspecific immunity -typically acts near entry points into the body and is always ready -antimicrobial molecules -various phagocytes -dendritic cells/macrohpages activate inflamm response (secrete cytokines) -phagocytes (monocytes and neutrophils are recruited)
What happens int he partial pressure of CO2 in blood rises?
condition = hypercarbia, or hypercapnia -RR will increase so that more CO2 is exhaled, causing CO2 levels in blood to fall -cells can also respond to changes in oxygen conc, happens during periods of sig hypoxemia (low O conc in blood)
cretinism
condition of congenital hypothyroidism in children that results in a lack of mental development and dwarfed physical stature; the thyroid gland is either congenitally absent or imperfectly developed
bone
connective tissue derived from embryonic mesoderm
stratum basale
contains STEM cells responsible for proliferation of KERATINOCYTES (predominant cells of skin that produce KERATIN)
H-zone
contains only thick filaments
A-band
contains thick filaments in their entirety, including any overlap with thin filaments
stratum corneum
contains up to several dozen layers of flattened keratinocytes, forming a barrier that prevents invasion by pathogens and that helps to prevent loss of fluids and salt hair projects over skin and there are openings for sweat and sebaceous glands
what is all muscle capable of and what does it rely on?
contraction and it relies on calcium
What are the parts of the adrenal glands and what do they secrete?
cortex and medulla Corticosteroids
What hormone increases the synthesis of catecholamines?
cortisol -increases the catecholamine release
list epithelial cell shapes
cuboidal columnar squamous
What are the molecules responsible for the cell cycle?
cyclins and cyclindependent kinases (CDK) 1.The right cyclins are required to be preset to ACTIVATE CDKs 2. cyclins bind to CDK creating an activated CDK-cyclin complex 3. complex can then phosphorylate transcription factors 4. Transcription factors promote transcription of genes requires for next stage of cell cycle (during the cell cycle, levels of various cyclins increase and decrease during specific stages)
inborn errors of metabolism
deleterious mutations defects in genes required for metabolism
What day of the menstrual cycle is a secondary oocyte ovulated from the follicle
day 14
When do LH levels peak?
day 14
when do FSH levels peak?
day 14
metabolic acidosis
decreased pH in blood and body tissues as a result of an upset in metabolism -not caused by hypoventilation
flexor muscle
decreases angle across jiont
what are the strata of the epidermis?
deepest stratum BASALE stratum SPINOSUM stratum GRANULOSUM stratum LUCIDUM stratum CORNEUM most superficial
What causes dwarfism?
deficuits of GH before closure of epiphyseal plates
Z-line (disc)
define boundaries of each sarcomere
Nucleolus
dense body visible in a non dividing nucleus; site of ribosomal RNA )rRNA) synthesis 25% of nucleus dark body
medial and lateral rotation
describes motion that occurs in limbrs medial: rotates axis of limb toward the midline lateral rotator rotateesaxis of limb away from midline
positive sense RNa virus
describes the genome of an RNA virus containing RNA that serves directly as the transcript for viral protein production -just like mRNA -single stranded RNA viruses can be positive or negative sense
adaptive radiation
describes the rapid rise of a number of different species from a common ancestor allows for various species to occupy different niches niche: specific enviro, including habitat, available resources, and predators, for which a species is specifically adapted favored by enviro changes or isolation of small groups of ancestral species
hemizygous
descriptor of males with respect to many of the genes on the X chromosome because they only have one copy Male with disease-causing allele on the unpaired part of X chromosome will necessarily express that allele
what is the muscular lining of the bladder?
detrusor muscle
What do chorionic villi develop into?
develop into the placenta -they support maternal-fetal gas exchange
mesoderm
develops into several different systems including musculoskeletal, circulatory, and most of the excretory systems -also gives rise to gonads, muscular and CT tissues layers, and respiratory systems and adrenal cortex means of getting around
isolation
differences in population so that they can no longer interbreed
What is the preferred method to move nutrients and waste regarding water, glucose, AA, and inorganic salts?
diffusion
what enzymes digest... disaccharides maltose isomaltose lactose sucrose
disaccharidases maltase isomaltse lactase sucrase -lack of disaccharidases causes inability to breakdown, allows hydrolysis produces methane (g)
what does the dissociation of ADP and inorganic phosphate form the mysoin head do?
dissociation of ADP and inorganic from myosin causes power strokes
After PCT, where does filtrate go?
distal convoluting tubules
patterns of evolution
divergent evolution parallel evolution convergent evolution
high frequency of recombination
donor's fertility plasmid has been integrated into the bacterial chromosome. May break part of donor chromosome off so only some of chromosome is transferred
What coats each alveoli?
each alveoli is coated in SURFACTANT--a detergent that lowers surface tension and prevents alveolus from collapsing on itself
what transfers pancreatic juices to the pancreas
duct system that runs through middle of pancreas acinar cells dump products into ducts ducts empty into duodenum through Major and Minor Duodenal Papillae
What is the response of hemoglobin to an increase in altitude?
due to decreased CO2 in enviro, decrease unloading of O so body would make more RBCs to ensure adequate delivery of O (could even increase valscualization)
segments of duodenum?
duidenum jejunum, ileum -total: up to 7 meters
dipeptidase
duodenum cleave peptide bonds of dipeptides to release free AA -proteins can be broken down into di/tripeptides and can be absorbed across the small intestine wall
enteropeptidase ("enterokinase")
duodenum enzyme critical for the activation of TRYPSINOGEN to TRYPSIN trypsinogen is a pancreatic protease --trypsin initiates activation cascade -ACTIVATE Procarboxypeptidases A and B to active forms
How does the body try to prevent autoimmune disorders?
during T-cell education in the thymus, T-cells that react to self-antigens are destroyed via negative selection B-cells that respond to self-antigens are elimed before they leave the bone marrow system not perfect...autoimmune
When is glucagon secreted?
during times of fasting -glucose levels are low so glucagon increases glucose by triggering GLYCOGENOLYSIS, GLUCONEOGENESIS, and DEGRADATION of protein and fat
what is the in the middle of each villus?
each villus has a capillary bed in the middle for absorption of water-soluble nutrients and a LACTEAL (lymphatic channel that takes up fats for transport into the lymphatic system)
primary germ layers
ectoderm, mesoderm, endoderm
after blood passes through the glomerulus what arterioles form the second capillary bed and what is it called?
efferent arterioles form a second capillary bed which surrounds the loop of Henle and is called VASA RECTA
bone marrow
either Red or yellow red: filled with hemipoietic stem cells which are responsible for the generation of all the cells in our blood yellow: composed primarily of fat and is relatively inactive
What is the embryo supported by until the placenta is functional?
embryo is supported by the yolk sac yolk sac is also a site of early blood cell development
origin
end of muscle with larger attachment (usually proximal)
When (fallaciously) do ppl think mitochondria originated?
engulfing and aerobic prokaryote by an anaerobic prokaryote resulted in a symbiotic relationship.
Acromegaly
enlargement of the extremities
where do the lacteals converge?
enter venous circulation at the thoracic duct in the base of the neck, empties into left subclavian vein
what is the pancreatic "master switch"
enteropeptidase (produced by duodenum) because it converts trypsinogen to trypsin which then coverts/ activates the other enzymes
Chemical digestion
enzymatic cleavage of chemical bonds, such as peptide bonds of proteins or glycosidic bonds of starches
As sperm are formed where do they pass through?
epididymis -place where sperm's flagella gain MOTILITY
Where does bone growth originate /
epiphyseal plates (seal shut during puberty)
What are the 4 types of tissue?
epithelial, connective, muscle, and nervous
What is the problem with crossing RH - maternal blood with RH + fetal blood?
erythroblastosis fetalis -anti-RH antibodies cross placenta and attack the fetal blood cells resulting in the hemolysis of fetal cells
What hormones do the ovaries secrete in response to gonadotropins?
estrogen and progesterone
What are estrogens secreted in response to?
estrogen secreted in reseponse to FSH -result = dev/maintenance of female repro system and femal secondary sexual characteristics -in EMBRYO, estrogens stim dev of repro tract -in ADULTS, estrogens promote thickening of the lining of uterus (ENDOMETRIUM) in prep for zygote implantation
What causes gigantism?
excess of GH released in childhood before close of epiphyseal plates
bacteria can switch between aerobic/anaerobic metabolism
facultative anaerobes
how are hormones released to their target tissue?
exocytosis
What type of invaders is inflammation particularly useful against?
extracellular pathogens. Bacteria, fungi, and parasites
allantois
extraembryonic membrane involved in early fluid exchange between the embryo and the yolk sac
Amnion
extraembryonic membrane that surrounds the allantois -thin, tough membrane filled with amniotic fluid (fluid serves as a shock aborber during pregnancy, lessening the impact of maternal motion on the developing embryo
founder effect
extreme case of genetic drift small population of a species finds itself in repro isolation as result of natural barriers, catastrophic events, or other BOTTLENECKS that drastically and suddenly reduce size of population available fro breeding causes inbreeding--> encourages homozygosity
What is the depolarized and impenetrable membrane called?
fertilization membrane
where does filtrate from the PCT go?
filtrate from the PCT travels to the Descending Limb of the Loop of Henle (which dives deep into the medulla before turning around to become the ASCENDING Limb of the Loop of Henle
What are women recommended to take to prevent spinabifida or ancephaly?
folate (folic acid)
liver can uptake glucose to...
for glycogen -can also store fats as triacylglycerols -also glycogenolysis, gluconeogenesis, mobilize fats in lipoproteins
haversian systems
found in the compact bone and are composed of concentric circles called lamellae
what allows filtrate to not cause swelling in of capsule or capillaries?
filtrate is ISOtonic
what are the 3 processes the kidney uses to regulate water
filtration, secretion, reabsorption
genetic LEAKAGE
flow of genes between species produce hybrid, when hybrid mates, leakage
list steps of post infection translation and progeny assembly
for translation -translocation of genetic material to the correct location in the cell (usually go to nucleus for mRNA transcription) -mRNA goes to cytoplasm where it is translated into protein by host ribosomes -neg sense RNA viruses require synthesis of a complementary RNa strand via RNA REPLICASE (DNA formed through reverse transcription in retroviruses also travels to the nucleus where it is integrated into host genome) Viral RNA is translated into protein by ribosomes, tRNA, AA, and enzymes of host cell -viral genome MUST return to its original form before packaging
what are calluses made of
form from excessive keratin deposition in areas of repeated strain due to friction -provide protection to avoid damage in the future -fingernails and hair are also formed from keratin and are produced by specialized cells in the skin
speciation
formation of a new species through evolution
menstrural cycle
from menarche to menopause -estrogen and progesterone levels rise and fall -divided into 4 events -follicular phase -ovulation -luteal phase -menstruation
Where does MEIOSIS occur?
gametocytes (germ cells) -result = up to 4 nonidentical sex cells (gametes)
point mutation
gene mutation in which a single base pair in DNA has been changed -silent missense nonsense
What are the coding regions of DNA (genetic material)?
genes gene: the basic unit of heredity; a region on a chromosome that codes for a specific product
transposon
genetic element capable of inserting and removing themselves from the genome -both prokaryotes and eukaryotes -can disrupt gene
renal corpuscle
glomerulus and bowman's capsule
counterregulatory hormones
glucagon, epinephrine, growth hormone, cortisol raise the blood glucose levels
What hormones does the adrenal cortex produce?
glucocorticoids (cortisol, cortisone) mineralocorticoids (aldosterone) (both steroids)
how are autoimmune cases treated?
glucocorticoids (modified cortisol) -potent immunosuppressent qualities
What are the 3 functional classes of corticosteroids?
glucosteroids mineralcorticoid cortical sex hormones
What organelle has stacked membrane-bound sacs?
golgi: organelle that plays a role int he packaging and secretion of proteins and other molecules produce intracellularly (vesicles come into cis-golgi and leave from trans-golgi)
Where are steroid hormones primarily produced?
gonads adrenal cortex
what does each nerve terminal control?
group of myocytes
Why is human chorionic gonadotropin (hCG) important in early pregnancy?
hCG maintains corpus luteum -corpus luteum secretes Estrogen and Progesterone which keep the uterine lining in place
what are the 3 components of the cardiovascular system?
heart, blood vessels, blood
What is the common precursor of both granulocytes and agranulocytes?
hematopoietic stem cells -also gives rise to RBCs
stomach
highly muscular organ with a capacity of approx 2 L -mucosa thick to prevent autodigestion
Metaphase I
homologous pairs (tetrads) align at METHPHASE PLATE and each pair attaches to a separate sindle fiber by its KINETOCHORE
Anaphase I
homologous pairs separate and are pulled to opp poles of the cell (DISJUNCTION) Disjunction accounts for MENDEL's first law (of segregation) -(during disjunction)---each chromosome of paternal origin disjoins from its homologue of maternal origin. -either chromosome can end up in either daughter cell -distribution of homologous chromosomes to the 2 intermediate daughter ells is RANDOM with respect to parental origin -separating of 2 homologous chromosomes = SEGREGATION
What do the glands in the endocrine system secrete?
hormones
What is hematopoiesis triggered by?
hormones, growth factors, cyctokines, **erythroppoietin (secreted by Kidney and stims RBC dev) **Thrombopoietin (secreted by Liver and KIDney and stims platelet dev
allele frequency
how often an allele appears in a population -does not indicate which flowers contain allele or if flowers are homo/hetero ONLY tells representation of allele across all chromosomes in population
what type of immunity is likely to be affected by the removal of the spleen?
humoral immunity
list layers of skin from deepest to most superficial
hypodermis (subQ layer) dermis epidermis -skin is derived from the ectoderm
What is the blood vessel system that directly connects the hypothalamus with the Anterior Pituitary?
hypophyseal portal system -blood vessels system that directly connects the hypothalamus with the anterior pituitary -keeps hormones released from hypothalamus form systemic circulation
What is another name for the pituitary?
hypophysis
What cerebral structure is the bridge between the nervous and endocrine systems?
hypothalamus
list some endocrine organs
hypothalamus pituitary thyroid parathyroid glands adrenal glands pancreas gonads pineal gland
monozygotic twins
identical twins formed when one zygote splits into two separate masses of cells, each of which develops into a separate embryo -incomplete division = conjoined twins monochorionic/monoamniotic twins -share the same amnions and chorion Monochorinon/diamniotic -share chorion, diff amnions Dichorionic/diamniotic - each has their own chorion and type of twinning comes form when SEPARATION occurred
ETC in bacterial located
in cell membrane
reductional division
in meiosis I, homologous chromosomes are separated generating haploid daughter cells (contrasts with division in MITOSIS)
movable joints
include hinge jionts, ball-and-socket jionts, permit bones to shift relative to one another strengthened by LIGAMENTS consist of SYNOVIAL capsule (which encloses the actual joint cavity (articular cavity) layer of soft tissue (SYNOVIUM) secretes Synocial fluid which lubricates the movement of structures in the joint space
prions
infectious proteins...nonliving trigger misfolding usually from alpha helix to beta sheet (decreases solubility of protein/ability to degrade protein) then protein aggregates form--interfering with cell function bovine spongiform encephalopathy creutzfeldt-Jakob Disease familial fatal insomnia
What will happen if there are increased levels of T3 or T4?
increased cellular respiration -leads to INCREASED protein and FA turnover by speeding up synth/degradation of these compounds -High plasma levels of T3 and T4 lead to decreased TSH and TRH (thyrotropin releasing hormone) synth -hypothalamic nuclei secrete TRH into portal vessel stinulating cells in AntPit to secrete TSH
What does increased intensity of a stimulus (AP) result in?
increased frequency of firing -NOT increase potential difference
how does epi increase HR and contractility in cardiac muscle
increases intracellular Ca levels within cardiac myocytes
extensor muscle
increases or straightens an angle across a joint
What does Antidiuretic Hormone (ADH) (Vasopressin) do?
increases the reabsorption of water int he collecting ducts of the kidneys -secreted in response to INCREASED plasma osmolarity
What are the two types of cleavage?
indeterminate determinate
progression of swallowing?
initiated by muscles in oropharynx--> upper esophageal sphincter -bolus moves toward stomach -lower esophageal sphincter (cardiac sphincter) relaxes and opens to allow passage of food
what does keratin provide protection from
injury, water, pathogens
What are the concentrations of Na in and outside a neuron?
inside: 12mM Outside: 145mM
What type of hormones are insulin, estrogen, and teesttosterone?
insulin = peptide estrogen/testosterone = steroid
how are the muscle cells in the heart connected?
intercalcated discs
how are muscle cells in cardiac muscle connected?
intercalcated discs -contain GAP JUCTIONS (connections between cytoplasm of adjacent cells, allowing for the flow of ions directly between cells) -allows for rapid and coordinated depolarization of cell and Efficient contraction
Smooth muscle
involuntary action autonomic nervous system respiratory tree, digestive tract, bladder, uterus, blood vessel walls, other... -single nucleus -actin and myosin -fibers not well organized, NO striation -maintain constant state of low-level contraction=TONUS (ex: blood vessel) -Myogenic acitvity: can contract w/o nervous input (contract directly in response to stretch or other stimuli)
what do cells infected with viruses produce to prevent further viral replication and dispersion?
interferons -cause nearby cells to decrease production of viral and cellular proteins -decrease permeability of these cells (harder to virus to infect other cells) -upregulate MHC class I and II --> increased antigen presentation and better detection of infected cells by immune system -responsible for "flul-like" symptoms (malaise, tiredness, muscle soreness, fever)
which muscles can speed up exhalation?
internal intercostal muscles and abdominal muscles
Location of Bundle of His
interventricular septum
where do simple carbs and AA go from the epithelial cells?
intestinal capillaries -blood always will have a lower concentration of these molecules so they diffuse into capillaries -absorbed molecules then go into liver via hepatic portal circulation
Besides HCl, what else do parietal cells secrete?
intrinsic factor -glycoprotein involved in the proper absorption of vit B12
What activates eosinophils?
invasive parasites and allergens
involvement of parasympathetic system in digestion?
involved in stimulation of digestive activities -increases secretions from exocrine glands -promotes peristalsis -sympathetic division is involved in inbititing this -all glands of body (except SWEAT glands) are innervated by parasympathetic nervous system
digestion
involves the breakdown of food into its constituent organic molecules: starches and other carbohydrates into monosaccharides, lipids (fats) into FFA and glycerol, and proteins into AA. 1. mechanical 2. chemical
absorption (contrast with digestion)
involves the transport of products of digestion from the digestive tract into the circulatory system for distribution to the body's tissues and cells
AV node location?
junction of atria and ventricles -signal delayed here to allow filling of ventricles completely before contraction
stabilizing selection
keeps phenotypes within a specific range by selecting against extremes
what is the predominant cell type in the epidermis?
keratinocytes
stratum granulosum
keratinocytes die and lose their nuclei
list some organs that have endocrine roles
kidneys, gastrointestinal glands, heart, thymus
excretory system functions?
kidneys, ureters, bladder, urethra
phases of growth
lag log/exponential stationary death
Secondary Response
later interactions with the same foreign substance; faster and more effective due to "memory" more rapid and robust -dev of these lasting memory cells is the basis of efficacy of vaccination
hypodermis
layer of CT that connects the skin to the rest of the body (contains fat and fibrous tissue)
second pump of heart
left side receives oxygenated blood from the lungs via pulmonay veins and forces blood through aorta (systemic circulation)
What happens if the length of the axon is extended?
length increases, = higher resistance and Slower conduction However.... -greater CROSS-SECTION areas allow for FASTER propagation due to DECREASED resistance
recombination frequency
likelihood that 2 alleles are separated from each other during crossing over roughly proportional to the distance between the genes on the chromosome
plasma
liquid portion of blood -aqueous mixture of nutrients, salts, respiratory gases, hormones, and blood proteins (serum=plasma w/o clotting factors)
transforming principle
live viruses acquiring abilities and traits from dead viruses
accessory organs of digestion
liver, pancreas, gallbladder
axon
long appendage that terminates in close proximity to a target structure (muscle, land, or neuron)
haversian canals
longitudinal channels (those with an axis parallel to the bone)
If a surgeon clipped a dorsal root ganglion, what would be the consequence?
loss of sensation at that level
Where does extracellular digestion occur?
lumen of alimentary canal -"outside" world -alimentary runs from mouth to anus with sphincters inbetween
where do naive B-cells wait?
lymph nodes
Where do immune cells communicate and mount an attack from?
lymphnodes
List the agranulocytes
lymphocytes (T-cell and B-CEll) and monocytes (macrophages)
Which RBCs are agranulocytes?
lymphocytes and monocytes do NOT contain granules important in SPECIFIC IMMUNE response (body's targeted fight against particular pathogens (ie virus/bacteria))
why are sex-linked (X-linked) traits more common in males?
males have only 1 recessive allele (X) which is sufficient for expression of the recessive phenotype
What cells are antigens present in?
macrophages, dendritic cells. certain eipthelial cells, and some B-cells
sarcomere
made of thick and thin filaments thick --> organized into bundles of MYOSIN thin --> actin + troponin + tropomyosin Titin: acts as spring and anchors actin and myosin filaments together, preventing excessive stretching of muscle
What are B-cells considered when they leave the bone marrow ?
mature but naieve because they have not been exposed to an antigen -part of HUMORAL response
Oral cavity
mechanical and chemical digestion Mechanical: mastication, increases surface area to volume ratio for enzymatic activity, moderates size -saliva moisturizes and lubricates Chemical: relies on enzymes from SALIVA produced by 3 pairs of Salivary glands -salivary amylase and lipase
countercurrent multiplier system
mechanism associated with loops of Henle that creates a region having high interstitial fluid osmolarity in renal medulla -vasa recta + nephron -flow of filtrate through loop of henle is opp that of direction of flow through vasa recta -ensures filtrate always exposed to hypertonic blood which alows maximal reabsorption of H2O
where are melanocytes derived from?
melanocytes are derived from neural crest cells and in stratum BASALE -produce MELANIN (pigment serves to protect skin from DNA damage casued by ultraviolet radiation)
archenteron
membrane invagination into the blastocoel which later develops into the gut -Blastopore: the opening of the archenteron - develops into anus in humans - in Protostomes it develops into the mouth
lysosomes
membrane-bound structures containing hydrolytic enzymes that are capable of breaking down many different substrates, including substances ingested by endocytosis and cellular waste products autolysis of lysosome causes apoptosis
What doe memory B cells do?
memory B-cells form from B-cells exposed to antigen and lie in wiat for a second exposure to a given antigen to mount a rapid, robust response
which phase of meiosis does each of mendel's laws most closely correlate?
mendel's first law: Anaphase I Mendel's 2nd law: Prophase I
What type of cells develop into the notochord?
mesodermal cells -notochord devs on the lognitudinal axis just under the dorsal layer of the ectoderm (ectoderm forms over chord)
What are the 3 components of the cytoskeleton
microfilaments microtubules intermediate filaments
what cellular organelle is semi-autonomous?
mitochondria contain some of their own genes and replicate independently of nucleus via BINARY FISSION examples of cytoplasmic/extranuclear inheritance (extranuclear inheritance: the transmission of genetic material independent of the nucleus)
what type of cells is the epiphyseal plate filled with before adulthood?
mitotic cells that contribute to growth
sarcoplasm
modified cytoplasm located just outside the sarcoplasmic reticulum
abductor
moes a part of the body away from the midline
adductor
moves a part of the body toward the midline
What are the two types of twins?
monozygotic; dizygotic identical, fraternal
codominance
more than one dominant allele exists for a given gene EX: blood type AB
what chemical forms most of the inorganic component of bone?
most inorganic bone is composed of HYDROXYAPATITE crystals
other name for synaptic bouton in muscle?
motor end plate
What is the name for the nerve terminal and the myocytes?
motor unit
temporal summation (AP)
multiple signals are integrated during a relatively short period of time Ex: small # of excitatory signals firing same time cause firing to reach threshold
what are many myofibrils connected in parallel also called?
muscle fiber
antagonistic pairs
muscles that act on opposite sides of a joint one contracts and other relaxes muscles can also be synergistic
What insulates most mammalian nerve fibers?
myelin--a fatty membrane -purpose: PREVENT signal loss or crossing of signals -increases speed of conduction along axon
frameshift mutation
mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide subcat: insertion or deletion mutations
What is one of the most common mutations found in cancer?
mutation to the p53 gene called TP53 -allows damaged DNA to continue in cycle. Mutation accumulate an then the result is cancer. Cancerous cell the divides continuously -if damaged cells produce right factors (proteases tha can digest membranes or factors that encourage blood vessel formation), damaged cells can reach other tissues -local invasion/distant spread of cancer cells (distant= metastasis)
What MAINTAINS the electrical signal within one neuron?
myelin SHEATH
What are myofibrils surrounded by?
myofibrils are surrounded by covering SARCOPLASMIC RETICULUM (SR) SR -modified endoplasmic reticulum that contains a high concentration of Ca2+
episome
name for subset of plasmids that are capable of integrating into the genome of the bacterium.
What type of feedback loop keeps testosterone in check?
negative to the hypothalamus so that levels stay in check
modern synthesis theory
neo-darwinism -adds knowledge of genetic inheritance and changes in the gene pool to Darwin's original theory Darwin's update theory: when mutation or recombination results in a change that is favorable to the organism's repro success, that change is more likely to pass on to the next generation
What is the functional unit of the kidney?
nephrom -approx 1 mill in every kidney
synapse
nerve terminal synaptic cleft postsynaptic membrane (synapse) (neurotransmitters bind to postsynaptic cleft)
What is the end of the axon?
nerve terminal or synaptic bouton (knob) enlarged and flattened to max transmission and ensure proper release of neurotransmitters
What is the adrenal medulla a derivative of?
nervous system
List the granulocytes
neutrophils, eosinophils, basophils
Which WBCs are granulocytes?
neutrophils, eosinophils, basophils -contain granules that are toxic to invading microbes (released through exocytosis) -involved in INFLAMM response, Allergies, Pus formation, and destruction of bacteria and parasites
can B-cells be activated by cytotoxic T-lymphocytes?
no
Do all B-cells that are generated actively or constantly produce antibodies?
no -antibody production is a energetically expensive process, and not always needed
Are individual chromosomes visible with light microscopy during interphase?
no they are in a less condensed form = CHROMATIN Chromatin because DNA must be available to RNA polymerase to transcribe genes (however, during mitosis, helpful to condense DNaAinto chromosomes to avoid losing any genetic material during cellular division)
Are neurons the only cells in the nervous system?
no, also glial cells (neuroglia) support neurons
are the granulocytes involved in specific or nonspecific defense?
nonspecific
does any mechanical of chemical digestion occur in the esophagus?
nope
can a man ever pass down a sex-linked trait to his son?
nope (for the most part)
vibrissae
nose hairs
What is a collection of cell bodies in the CNS called?
nucleus
ploidy
number of sets of chromosomes in a cell
anaerobic bacteria that cannot be in presence of oxygen
obligate anaerobes presence of O leads to production of ROS which can lead to cell death
bacteria require oxygen for survival
obligate arerobes
deletion mutation
occurs when a large segment of DNA is lost from a chromosome small deletion mutations are considered frameshift mutations
incomplete dominance
occurs when heterozygote expresses a phenotype that is intermediate between 2 homozygous genotypes Pink flower
dizygotic twins
often called fraternal twins, occurring when two eggs each get fertilized by two different sperm, resulting in two zygotes in the uterus at the same time -each devs its own placenta, chorion, and amnion -no more genetically similar than any other set of siblings
What produces myelin?
oligodendrocytes in the CNS Schwann cell is PNS
stratum lucidum
only present in thick, hairless skin (sole of foot/palms). nearly transparent
Name the production of female gametes
oogenesis
anus
opening through which wastes are eliminated 2 sphincters -internal --involuntary control (autonomic) -external--voluntary control (somatic)
trace food's path through body
oral cavity pharynx esophagus stomach small intesting large intesting rectum enzymes and lubrication from -salivary glands -pancreas -liver -gallbladder
out-breeding
out-crossing introduction of unrelated individuals into a breeding group
trophoblast
outer cells of the blastocyst that secrete enzymes that allow implantation -specialized to create an interface between the maternal blood supply and the developing embryo
mitochondrioa membrane functions
outer: barrier between cytosol/inner enviro inner: cristae: contains molecules and enzymes of ETC. cristae folds increase SA for ETC enzymes. etc-->protons for proton motive force for ATP synthesis
ectoderm
outermost germ layer; produces sense organs, nerves, and outer layer of skin -integument, epidermis, hair, nails, and epithelia of nose/mouth/lower anal canal. lens of eye, nervous system (and adrenal medulla), inner ear
cecum
outpocketing that accepts fluid exiting the small intestine through the ILEOCECAL VALVE and is the site of attachment for APPENDIX
differential reproduction
over time, those traits passed on by the more successful organisms will become ubiquitous in the gene pool (gene pool changes over time, pops evolve, not individuals)
What is one way the gut prohibits foreign bacterial growth?
overcrowding of bacteria already found in the gut
Hardy-Weinberg equation
p + q = 1 (frequency of alleles in population) (p^2) + 2pq + (q^2) = 1 (freq of gene/phenotypes in pop) p^2 = frequency of homo dom genotype 2 pq = frequency of hetero dom genotype q^2 = frequency of homo rec genotype p^2 + 2 pq = represent frequency of dom phenotype p = dominant q= recessive 2x as many alleles in pop as individuals
how does pepsin cleave peptide bonds?
pepsin cleaves peptide bonds near aromatic AA resulting in short peptide fragments -most active at LOW pH
aminopeptidase
peptidase secreted by glands in duodenum that removes the N-terminal amino acid (duodenum)
What type of hormone can trigger a response that can increase in intensity at each step?
peptide hormone
secretin
peptide hormone -casues pancreatic enzymes to be released into duodenum -regulates pH of digestive tract by reducing HCl secretion from parietal cells and increasing bicarb secretion from pancreas hormone funciton -f as ENTEROGASTRONE--hormone that slows motility through the digestive tract (decreased motility allows increased time for digestive enzymes to act on chyme--especially fats)
what does parathyroid hormone do to bone?
peptide hormone released by parathyroid in response to LOW blood Ca -promotes resorption of bone, increasing concentration of Ca and phosphate in blood activates VIT D which promotes resorption of bone (encourages growth of new stronger bone.)
Are peptide hormones or steroid hormones faster to turn off/on
peptide hormones are faster to turn off/on, but effects do not last w/o relative constant stimulation -steroid hormones are slower but longer-lived
How long do the effects of peptide hormones usually last?
peptide hormones usually are rapid but short-lived because they use SECOND messenger cascades (which are transient)
What are common endings for peptide/AA-derivative hormones or Steroid hormones?
peptide/AA-derivative hormones -usually end in -in, or -ine steroid hormones -usually end in -one, -ol -oid
Importance of location of DNA in nucleus?
permits the compartmentalization of DNA transcription separate form RNA translation
mechanical digestion
physical breakdown of large food particles into smaller food particles--does NOT involve breaking chemical bonds
what happens to pigment from melanocytes once it is produced?
pigment is transferred to keratinocytes -humans generally have same # of melanocytes, activity level varies
How do arrector pili in the skin allow for thermoregulation?
piloerection allow for a layer of heated air to be trapped near skin -arterioles near skin also contract
What does the pineal gland secrete?
pineal gland (located deep in brain) secretes MELATONIN -involved in CIRCADIAN rhythms -receives direct projections from retina, NOT involved in vision
What do plasma cells do?
plasma cells form fromB-cells exposed to antigen and produce antibodies. plasma cells: differentiated immunoglobulin-secreting B-lymphocytes involved in humoral immunity
Bacterial DNA acquired from external sources...
plasmids -not considered part of the genome -may confer an advantage (antibiotic resistance)
how is the blood clot broken down
plasmin (generated from plasminogen)
What are the membranes that surround each lung?
plurae
osteoclasts
polynucleated resident macrophages of bone
Blood usually only goes through one capillary bed before returning to the heart except in the case of.....and list them
portal systems Hepatic portal system hypophyseal portal system renal portal system
What happens after cellular products are modified and sorted in the golgi?
repackaged in vesicles then directed to the correct cellular location if destined for secretion, secretory vesicle merges with the cell membrane and its contents are released via EXOCYTOSIS
What determines what tissues a particular stem cell can differentiate into?
potency: term used to describe the ability or inability of a stem cell to differentiate into different cell types -Greatest potency = TOTIpotency -include embryonic cells -can diff into any cell type either in fetus or in placental structures -16 cell stage of morulato innercell mass/trophoblast (becomes pluripotent after diff into 3 germ layers
what neurotransmitters do sympathetic nervous system release?
preganglionic release Acetylcholine postganglinic release norepi
brush border enzymes
present on the luminal surface of cells lining the DUODENUM and break down dimers and trimers of biomolecules into absorbable monomers -DISACCHARIDES: maltase, isoaltase, lactase, sucrase -PEPTIDASES: dipeptidase
What is the driving force of gas exchange in the lungs?
pressure differential (flows down partial pressure gradient)
what are the 2 ways reproductive isolation can occur
prezygotic mechanisms: prevent formation of the zygote completely -temporal isolation (breeding at diff times) -ecological isolation (living in different niches within the same territory) -behavioral isolation (lack of attraction between members) postzygotic mechanisms: allow for gamete fusion but yield either nonviable or sterile offspring -hybrid inviability: formation of zygote that cannot dev to term -hybrid sterility -hybrid breakdown (forming first generation hybrid offspring that can repro, but 2nd gen that cannot)
cardiac muscle
primarily UNInucleated (some cells contain 2) -contraction = involuntary autonomic nervous system appears striated DEFINE and MAINTAIN own RHYTHM -MYOGENIC ACTIVITY
germinal centers
primary locations where B lymphocytes reproduce and proliferate
During which phase of meiosis is the primary oocyte arrested? Secondary oocyte?
primary: Prophase I Secondary: Metaphase II
ribosome sizes of pro/eukaryotes
pro: 30/50 S Eu: 40/60S
parturition
process of giving birth vaginally -accomplished by rhythmic contractions of uterine smooth muscle
Bulbourethral (Cowper's) gland
produces a clear viscous fluid that cleans out any remnants of urine and lubricates the urethra during sexual arousal
What are progesterone secreted in response to?
progesterone secreted in response to LH -secreted by CORPUS LUTEUM (remains of the ovarian follicle following ovulation) -progesterone involved in dev/maintenance of ENDOmetrium (but NOT in initial thickening)) -BOTH estrogen and progesterone needed for dev/main. of endometrium -by end of 1st TRImester, progesterone supplied by placenta, (corpus luteum atrophies and ceases to f)
apoptosis (cell death)
programmed cell death -occurs various times of development -Ex: webbing in toes/fingers apop to allow fingers
What does GH do?
promote growth of BONE and MUSCLE -this growth = energetically expensive, requires lots of GLUCOSE -to increase glucose ava 1. prevents glucose uptake in certain tissues (those NOT growing) 2. Stims break down of FA -Stimmed by GHRH
Besides raising blood Ca levels, what does PTH do?
promotes phosphorus homeostasis by increasing resorption of PHOSPHATE from BONE and **reducing resorption of phosphate in KIDNEY (promotes its excretion)
What are contractions coordinated by?
prostaglandins -and peptide hormone, Oxytocin
components of a virus (obligate intracellular parasite, lack ribosomes)
protein coat (capsid) + nucleic acid + viral envelope derived from host's cell bacteriophage -nucleic acid, capsid, tail sheath, tail fibers
self-antigens
proteins and carbohydrates present on the surface of every cell of the body -usually signal that cell is NOT foreign and should NOT be attacked -if this fails = autoimmune
list the structures bowman's capsule leads to in order
proximal convoluted tubule descending/ascending limbs loop Henle distal convoluted tubule collecting duct
what arteries contain deoxy blood?
pulmonary umbilical
Which veins carry Oxy blood?
pulmonary and umbilical
What is the first pump in the heart?
pulmonary circulation -receives deoxygenated blood from the superior vena cava right side of heart
What is the valve that separates the right ventricle from the pulmonary circulation?
pulmonary valve
adrenal medulla
purpose: responsible for the production of the sympathetic hormones Epinephrine and Noreponephrine -specialized nerve cells in medulla can secrete these compounds directly into the bloodstream
through what structure does food leave the stomach?
pyloric sphincter then enters duodenum
biometric techniques
quantitative approaches to biological data -punnett squares -gene mapping -hardy-weinberg equilibrium
cleavage
rapid MITOTIC cell division of the zygote that begins immediately after fertilization while it is moving to the uterus for implantation
divergent evolution
refers to independent development of dissimilar characteristics in 2 or more lineages sharing a common ancestor
convergent evolution
refers to the independent development of similar characteristics in 2 or more lineages not sharing a recent common ancestor
parallel evolution
refers to the process whereby related species evolve in similar ways for a long period of time in response to analogous environmental selection pressures
I-Band
region containing exclusively thin filaments
hat is the primary job of the kidney
regulate blood volume and osmolarity
trace the events that initiate muscle contraction in order
release acetylcholine from motor neuron activation of acetylchoilne receptors in sarcolemma depolarization of sarcolemma spreading of signal using T-tubules release of Ca from SR binding of Ca to troponin conformational shift in tropomyosin exposure of myosin-binding sites myosin binds to actin
List the vessels in the renal vascular pathway, starting from the renal artery
renal artery afferent arteriole glomerulus efferent arteriole vasa recta renal vein
what is the deep slit in the center of the medial surface of the kidney
renal hilum
where do nephrons empty into?
renal pelvis which narrows to form the ureter
shivering
requires sizable amount of ATP, converted to thermal energy
What two systems does the bicarbonate buffer system link?
respiratory and renal systems -if someone is hyperventilating and blowing off CO2, then kidney can compensate by excreting bicarbonate to bring pH back down Ex: renal tubular acidosis type I -kideny unable to excrete acid effectively, so excess CO2 can be exhaled increase RR
What systems are most affected by premature birth?
respiratory, gastrointestinal, and nervous
simple twitch
response of a single muscle fiber to a brief stimulus at or above threshold LATENT period: time between reaching threshold and onset of contraction. AP spreads along muscle and allows Ca to be released from SR CONTRACTION period RELAXATION period
duodenum
responsible for maj of chem digestion and some absorption
(bacterial) transformation
results from the integration of foreign genetic material into the host genome -ususally occurs when bacterium lysis in vicinity of bacteria capable of transformation -common process in gram-negative rods
indeterminante cleavage
results in cells that can still develop into complete organisms -monozygotic twins have identical genomes because they both originate from indeterminately cleaved cells of same embryo
determinate cleavage
results in cells with fates that are already determined -cells are committed to differentiating into a certain type of cell
Meiosis
results in homologous chromosomes being separate generating haploid daughter cells
emesis (vomiting)
reversal of peristalsis -triggered by: exposure to chemicals, infectionous agents, physical stimulation in posterior pharynx, cognitive stimulation
SA node location?
right atrium
what direction does the oxyhemoglobin dissociation curve under go when there is an excess of CO2 present in the muscle?
right shift in the presence of CO2, increased H+ conc, and increased temp
what is the lining of the stomach called?
rugae
M-line
runs down the center of the sarcomere, through the middle of the myosin filaments
Which salivary enyzme is capable of hydrolyzing starch into smaller sugars (maltose/dextrins)
salivary amylase
Where is starch hydrolyzed into maltose?
salivary amylase in MOUTH pancreatic amylase from pancreas in DUODENUM
what can the nephrons secrete?
salt, acids, bases, and urea secretes by active or passive transport -quantity and identity of substances secreted into nephron are directly related to the needs to the body at that time -can also secrete wastes, K +, H+, or metabolites of medications (especially if they are too large to pass through glomerular pores -secretion: movement of solutes from blood to filtrate anywhere besides bowman's capsule
what is the cell membrane of the myocyte?
sarcolemma capable of propagating an AP and can distribut the AP to all sarcomeres in a muscle using transverse tubules (T-tubules) that are oriented perpendicularly to the myofibrils
what is the basic contractile unit of skeletal muscle?
sarcomere
sarcomeres attached end to end
sarcomeres are attached end -to-end to form MYOFIBRILS
Where are the testes located?
scrotum -an external pouch that hangs below penis -position allows it to maintain temp 2-4 degrees C lower than body -layer of muscle around vas deferens (ductus deferens) that raises/lowers testis to maintain proper temp for sperm dev
What happens after ovulation?
secondary oocyte travels into the fallopian tube where it can be fertilized up to 24 hours after ovulation
what are DIRECT hormones?
secreted the act DIRECTLY on target tissue Ex: insulin from pancreas increases uptake glucose by muscles
translocation mutations
segment of DNA from 1 chromosome is SWAPPED with a segment of DNA from another chromosome
duplication mutation
segment of DNA is copied multiple times in the genome
insertion mutation
segment of DNA is moved from one chromosome to another small insertions are considered frameshift
inversion mutations
segment of DNA is reversed within chromosome
what separates the ventricles from the vasculature?
semilunar valves
What are the types of nerves in the PNS that are bundled together?
sensory motor mixed cell bodies of these neurons are clustered together to form ganglia
What are the 3 types of neurons?
sensory motor internuerons
Where are products from the ER sent?
sent to GOLGI in vesicles once inside, cellular products may be modified by addition of groups like carbohydrates, phosphates, and sulfates
where does the neural signal travel after it leaves the neuromuscular junction?
signal travels down until it reaches the nerve terminal (SYNAPTIC BOUTON) -this is where acetylcholine is released into the synapse -acetylcholine binds to receptors on the sarcolemma, causing depolarization
hormones
signaling molecules that are secreted DIRECTLY into the BLOODSTREAM to DISTANT target tissues -bind to receptors --> gene in gene expression or cellular functioning
binary fission
simple form of asexual repro in prokaryotes -circular chromosome attaches to CW and replicates while cells grow
what molecules and how are they absorbed by the small intestine?
simple sugars (glucose, fructose, AA) -absorbed by the secondary active transport and facilitated diffusion into epithelial cells lining the small intestine -then substances move across epithelial cells into Intestinal capillaries
list epithelial layers of cells classifications
simple; 1 layer stratified: have more than 1 layer pseudostratified: appear to have multiple layers, but only one (diff in cell height)
What is the first line of defense
skin (integument) -physical barrier, prevents most bacteria, virus, fungi, and parasites from entering the body -DEFENSINS on skin -- antibacterial enzymes -sweat has antimicrobial properies
axial skeleton
skull, vertebral column, ribcage, and hyoid bone provides basic central framework for hte body
appendix
small fingerlike projection that was once thought to be vestigial -may have tole in warding off certain bacterial infections, repop large intestine with normal flora after diarrhea
where are vitamins absorbed?
small intestine
viroids
small pathogens consisting of very short circular single-stranded RNA that infect plants can bind to may RNA sequences and can silence genes in plant genome --> prevents synth of necess. proteins =metabolic/structural damage to cell Hep D, if coinfected with hep B, causes silencing in human hepatocytes.
what lies between the lamellar rings?
small spaces called LACUNAE, which house mature bone cells known as OSTEOCYTES
lymph nodes
small, bean-shaped structures along the lymphtic vessels -contain a lymphatic channel as well as an artery and a vein -they provide a space fro cells of the immune system to be exposed to possible pathogens
How does Na get into neurons?
sodium leak channels Equib potential: 60mV (POS bec NA moving INTO cell)
Where is the nucleus of the neuron located?
soma (cell body) -soma also = location of ER and ribosomes
What control (somatic or autonomic) is the diaphragm under?
somatic
what inhibits GH?
somatostatin
reabsorption
some coumpounds that are filtered by nephrons or secreted ban be taken back up for use -movement of solutes from filtrate to blood
Where is blood stored and B-cells activated?
spleen -filters the blood and lymph -site where an immune response can be mounted
langerhans cells (in skin)
special MACROPHAGES that reside in stratum SPINOSUM -capable of presenting antigens to T-cells in order to activate immune system
Neurons
specialized cells capable of transmitting electrical impulses and then translating those electrical impulse into chemical signals
humoral immunity
specific immunity produced by B CELLS that produce ANTIBODIES that circulate in body fluids
humoral immunity
specific immunity produced by B CELLS that produce ANTIBODIES that circulate in body fluids because antibodies dissolve into the humor.fluid -take as long as week to become fully effective after initial infection originate and mature in BONE MARROW -Activated in spleen and Lymphnodes
What are the three stages of cell specialization?
specification, determination, differentiation
What are diploid stem cells in males called?
spermatogonia
What condition is marked by a failure of the neural tube to close?
spina bifida (spinal cord exposed to outside world) -range of severity or Ancephaly (brain fails to dev and skull left open (universally fatal)
Where are the axons of motor and sensory neurons located?
spinal cord
The chemical digestion of carbohydrates is started and finished where?
started: in mouth completed: in intestines
What happens to the size of the embryo the first few divisions?
stays the same -divides in to progressively smaller cells
Why are the effects of steroid hormones longer lasting than peptide hormones?
steroid hormones participate in gene regulation, causing alterations in the amount of mRNA and protein present in a cell by direct action on DNA
How to steroid hormones travel?
steroid hormones travel by CARRIER proteins in the BLOODSTREAM since they are not water-sol -some proteins are very specific and only carry 1 hormone (sex hormone-binding globulin -some proteins are not specific in what they carry (albumin)
What does Oxytocin do?
stimulates uterine contractions during labor as well as milk letdown during lactation -involved in bonding behavior
When the bladder is full...
stretch receptors --> tell nervous system bladder needs emptying-->parasymph neruons fire --> detrusor muscle contracts--> causes internal sphincter to relax micturition reflex then can choose to release external sphincter or not
purpose of cellular cytoskeleton
structure/shape provides conduit for transport of materials around cell
antigen
substance (usually pathogenic protein) that can be targeted by an antibody mainly in adaptive immune system, innate immune system can also present antigens
purpose of Connectie tissue
support body provide framework for epithelial tissue to carry out functions mainly contributes to stroma (support structure) ex: bone, cartilage, tendons, ligaments, adipose tissue, and blood most CT produce/secrete materials such as collagen and elastin to form extracellular martix
what part of the hypothalamus receives some of the light input form the retinae and helps control sleep-wake cycle?
suprachiasmatic nucleus
natural selection
survival of the fittest theory that certain characteristics or traits possessed by individuals within a species may help those individuals have greater reproductive success, thus passing on those traits to offspring -organisms produce offspring, few survive to repro maturity -chance variations within individuals in pop may be heritable, if variation = adv then it is favorable -individuals with greater preponderance of favorable variations = more likely to survive, increase in traits in future generations -level of repro success = FITNESS
what actions help with thermoregulation via dermis?
sweating piloerection vasodilation vasoconstriction
What are the two divisions of the ANS?
sympathetic and parasympathetic -ANTAGONISTIC --act in opp of each other
What happens if BP too high?
sympathetic impulses could decrease -allows relaxation of vasculature with concerrent drop in BP HEART -releases Atrial Natruiretic peptide (ANP) -weak diruetic, aids in salt loss from kidneys (not usually enough to counter high sodium intake)
Prophase I Diplotene
synapsis ends with the disappearance of the synaptonemal complex; homologous pairs remain attached at chiasmata
How are water soluble vitamins absorbed?
taken up along with H2O, AA, and carbohydrates across endothelial cells of small intestine, passing directly into plasma
What causes detrimental effects during organogenesis?
teratogens: substances that interfere with dev, causing defets or even death of dev embryo - the unique genetics of the embryo influences the effects of the teratogen other influences -route of exposure, length of exposure, rate of placental transmission of the tertogen, exact identity of the teratogen Ex: alcohol, prescription drugs, viruses, bacteria, enviromental chemicals including polycyclic aromatic hydrocarbons
constant region (domain) of an antibody
terminal that contains 2 heavy chains; remains same for certain class of antibodies; determines characteristics (class) of antibody; where complement binding takes place -this regions is the one that NK, macrophages, monocytes, and eosinophils have receptors for and can initiate the complement cascade -IgM, IgD, IgG, IgE, IgA
What do the primitie gonads develop into in males?
testes--which have 2 functional parts 1. seminferous tubules : where sperm are produced. highly coiled. Nourished by SERTOLI CELLS 2. Interstitial cells of Leydig: secrete TESTOSTERONE and other male sex hormones (ANDROGENS)
Expiratory Reserve Volume (ERV)
the Volume of additional air that can be FORCIBLY EXhaled after a normal exhalation
Meiosis II
the second phase of meiosis consisting of chromatids separating, along with the two diploid cells splitting in two -diff than mitosis bec SISITER CHromatids (no homologues) separate from each other
oxygen debt
the amount of oxygen required after physical exercise to convert accumulated lactic acid to glucose diff between amount of oxygen needed by muscles and actual amount present
What happens if the antibody is on the cell-surface and binds an antigen?
the binding of an antige to a B-cell causes activation of that cell resulting inits proliferation and formation of a plasma memory cell
phenotype
the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.
what happens when the endothelium is damaged?
the connective tissue underneath is exposed with contains collagen and a protein called TISSUE FACTOR -platelets sense damage when come into contact with CT and begin to aggregate and coagulate -COAGULATION factors (secreted by liver) sense tissue factor and initiate a complex activation cascade
test cross
the crossing of an individual of unknown genotype with a homozygous recessive individual to determine the unknown genotype if homo dom all = dom phenotye if hetero then 1:1
molecular clock model
the degree of difference in the genome between two species is related to the amount of time since the two species broke off from a common ancestor
Vital capacity (VC)
the difference between the minimum and maximum volume of air in the lungs (TLC - RV)
hydrostatic pressure
the force per unit area that the blood exerts against the vessel walls -generated by the contraction of the heart and the elasticity of the arteries -measured upstream in large quantities as BP -pushes fluid out of bloodstream into the interstitium through the capillary walls (leaky)
spermatogenesis
the formation of haploid sperm through meiosis -occurs in seminiferous tubules spermatogonia (after replicating their genetic material (S Stage) develop into DIPloid PRIMARY SPERMATOCYTES -Meiotic division of primary spermatocytes results in HAPloid SECONDARY SPERMATOCYTES -2ndary Spermatocytes undergo Meiosis II to generate HAPloid SPERMATIDS -Spermatids mature to become SPERMATOZOA -spermatogenesis results in 4 functional sperm for each spermatogonium
when actin is exposed...
the free globular heads of the myosin molecules move toward and bind with the exposed sites on actin myosin heads can then pull on the actin drawing towards M-line and making the H-zone smaller
What triggers the testes to secret testosterone?
the gonadotropins of LH and FSH
What happens at the end of Meiosis II with the sperm and ovum?
the haploid PRONUCLEI of sperm and ovum join to create a DIploid ZYGOTE
what structure restricts what hormone prior to puberty?
the hypothalamus restricts produciton of gonadotropin-releasing hormone (GnRH)
Mendel's second law (of independent assortment)
the inheritance of 1 gene does not affect the inheritance of another gene
endoderm
the inner germ layer that develops into the epithelial linings of the digestive/respiratory tracts, including lungs -also pancreas, thyroid, bladder, and distal urinary tracts, parts of liver
species
the largest group of organisms capable of breeding to form fertile offspring;
what compounds does the liver detoxify?
the liver detoxifies endogenous (made in body) and exogenous (brought in from enviro)
What are key factors that determination and differentiation rely on?
the location of the cells and the identity of the surrounding cells - developing cells receive signals form organizing cells around it and mayalso secrete its own signaling molecules (inducer can also refer to cell secreting signal)
how does the lymphatic system transport fats?
the lymphatic system transports fats via LACTEALS (small lymphatic vessels that are locate at the center of each Villus in the small intestine) -fats packaged into chylomicrons by intestinal mucosal cells enter the lacteal for transport -lymphatic fluid that carries chylomicrons is milky white and called CHYLE
besides fluid from the bloodstream, what else does the lymphatic system carry?
the lymphatic tissue transports fats from the digestive system into the bloodstream -
Total Lung Capacity (TLC)
the max volume of air in the lungs when one inhales completely; usually 6-7 L
Equilibrium potential of potassium
the membrane reaches a voltage at which there is an equilibrium between the concentration gradient that moves potassium out and the electrical gradient that moves potassium in -K+ can come back in due to NEG charge on inside of molecule...eventually no NET movement of ion Equib Potential = -90mV (NEG bec K is leaving)
pharynx
the membrane-lined cavity behind the nose and mouth, connecting them to the esophagus. -leads form mouth and posterior nasal cavity to esophagus -connects to larynx (part of respiratory tract) 3 parts -nasopharynx -oropharynx -laryngopharynx -EPIGLOTTIS prevents food in larynx (failure of this = choking)
How is the process of APOPTOSIS (programmed cellular death) started?
the mitochondrion releases the enzymes from the ETC
senescence
the natural physical decline brought about by aging, biological again -can occur at cellular or organismal level cellular level: failure to divide: normally after approx. 50 divisions in vitro (maybe due to shortened telomeres) (telomerase, reversetranscriptase that synth ends of promosomes preventing senesence, allows division indefinitely, may play role in cancer) Organismal: change in body's ability to respond to changing enviro
negative sense RNA virus
the negatie-sense RNa strand acts as a tmeplate for synthesis of a complementary strand, whcih can then be used as a template for protein synthesis. -must carry RNA REPLICASE in viron to ensure that complementary strand is synthesized
Resting membrane potential
the net electric potential difference that exists cross the cell membrane neurons: about -70mV (inside neuron NEG, relative to outside)
What do the neural folds do in neurulation?
the neurual folds grow TOGETHER and fuse into a NEURAL TUBE -Neural Tube gives rise to Central Nervous System -Tips of neural folds = neural crest
What is unique about mature RBCs?
the nuclei, mitochondria, and other membranes-bound organelles are lost Don't consume O2, so don't use oxidative phosphorylation Source of ATP = GLYCOLYSIS -lactic acid = main byproduct No nuclei = no division of the cell
oncotic pressure
the osmotic (sucking pressure that draws water into vasculature) that is attributable to dissolved proteins specifically -normal: 290 milliosmoles (mOsm) per Liter
epiblast
the outermost layer of an embryo before it differentiates into ectoderm and mesoderm.
what marks ovulation?
the peak of LH around day 14 ovulation= the release of the oocyte from the follicle
Where does fetal blood become oxygenated?
the placenta
Why is hCG not as important in the second trimester?
the placenta has grown to a sufficient size to secrete enough progesterone and estrogen by itself. -High levels of estrogen and progesterone continue to sere as NEG feedback on GnRH secretion
what causes the release of brush-border enzymes in the stomach?
the presence of chyme in the duodenum causes release of rush-border enzymes
How/when does male differentiation occur?
the presence of the Y chromosome causes the production of ANDROGEN the androgen results in male sexual differentiation from conception to birth. then infancy - childhood, testosterone produciton is low
Mitosis
the process by which 2 identical daughter cells are created from a single cell phases 1. prophase 2. metaphase 3. anaphase (4 chromosomes present) 4. telophase occurs in SOMATIC CELLS (cells NOT involved in sexual repro)
amniocentesis
the process of aspirating amniotic fluid by inserting a thin needle into the amniotic sac. sac contains fetal fetal cells. examined for chromosomal abnormalities and sex determination
in the kidney, what does the renal artery branch into?
the renal artery branches out, passes through the MEDULLA, and enters the Cortex as AFFERENT ARTERIOLES
passive immunity
the short-term immunity that results from the introduction of antibodies from another person or animal. -transient bec antibodies (not the plasma cells that produce them) are given to the individual. Ex: antibodies across placenta during pregnancy, breast milk Ex: case of rabies /tetanus, intravenous immunoglobulin may be given to prevent the pathogen from spreading
what happens to the solutes that are reabsorbed at the PCT?
the solutes that enter the interstitium (CT surrounding the nephron) are picked up by the vasa recta to be returned to the bloodstream for reuse within the body
What happens when sperm pass through the repro tract?
they are mixed with SEMINAL FLUID (produced through combined effort by seminal vesicles , prostate gland, and bulbouretheral gland) -both Seminal vesicles and Prostate gland give fluid mildly ALKALINE properties so sperm can survive in relative acidity of female repro tract
Menopause
the time of natural cessation of menstruation; also refers to the biological changes a woman experiences as her ability to reproduce declines -ovaries less sensitive to FSH and LH, result = ovarian atrophy -estrogen/progesterone leels drop, endometrium atrophies, menstration stops -bec ENG feedback on FSH an dLH removed, blood levels of those hormones increase
Transduction
the transposition of genetic material from one organism to another by a virus virus infects cell, both DNA fragment, repackage and lyse (bacteriophages)
Inspiratory Reserve Volume (IRV)
the volume of additional air that can be forcibly inhaled after a normal inhalation
Tidal Volume (TV)
the volume of air INhaled or EXhaled in a normal breath
Residual volume (RV)
the volume of air remaining in the lungs when one exhales COMPLETELY
What happens after sperm gain their motility?
they are stored in the epididymis until ejaculation
Besides gas exchange, what are some other functions of the respiratory system?
thermoregulation, immune function, control of blood pH
what do bile salts do?
they are AMPHIPATHIC molecules that can emulsify fat in the digestive system
What happens to naive T-cells
they are mature but once they are exposed to an antigen, the T-cells undergo CLONAL selection so that only those with the highest affinity for a given antigen proliferate
What structure do most of the lymphatic vessels join into?
thoracic duct thoracic duct is in the posterior chest and delivers the fluid into the left subclavian vein
Besides the addition of groups, how can the golgi modify cellular products?
through the introduction of signal sequences (which direct the delivery of the product to a specific cellular location )
where do the renal artery, renal vein, and ureter enter and exit the kidney?
through the renal hilum
Where do T-cells mature?
thymus (small GLAND infront of the pericardium)
Main role of parasympathetic nervous system
to conserve energy -associated with resting and sleeping states, REDUCES HR, Constricts Bronchi -manages digestion (increases peristalsis and exocrine secretions) -Acetylcholine responsible of PNS response in body (ACh released by both preganglionic neurons and postganglionic neurons)
suppressor (regulatory) T-cells
tone down the immune response after an infection and promote self-tolerance -have CD4 AND the express protein Foxp3 -turn off self-reactive lymphocytes to prevent autoimmune diseases --> "self-tolerance"
When does HYPOglucemia occur?
too much INSULIN
Where does the largest drop in BP occur in the vasculature?
transition from arteries to arterioles -arterioles decrease pressure because capillaries can't handle high pressures
Volkmann's canals
transverse channels (axis is perpendicular to bone)
Where does the blastua end up?
travels through the fallopian tube to the uterus and implants into the endometrium
pancreatic peptidases
trypsinogen chymotrypsinogen carboxypeptidases A and B released in Zymogen form -responsible for PROTEIN digestion
portal system
two capillary beds in series through which blood must travel before returning to the heart
homologues
two chromosomes that code for the same traits as itself; traits are same, but actual genes may be different all people inherit to alleles for all genes except for male sex chromosomes
what causes diabetes mellitus?
underproduction, insufficient secretion, or sensitivity to insulin -clinically characterized by HYPERglycemia
intramembranous ossification
undifferentiated embryonic connective tissue (mesenchymal tissue) is transformed into and replaced by bone (occurs in bones of skull)
cell-mediated immunity
type of immunity produced by T CELLS that ATTACK infected or abnormal body cells
What does grey matter consist of?
unmyelinated cell bodies and dendrites
liver
upper R quad of abdomen 2 unique structures for communicate with digest system 1. bile ducts connect the liver with both gallbladder and small intestine (bile produced in liver, stored gallblad) 2. liver receives ALL blood draining from abdominal portion of digestive tract through HEPATIC PORTAL VEIN (nutrient rich blood processed before draining into inferior Vena Cava to R side of heart)
location of stomach?
upper left side of abdomen, just below diaphragm
expressivity
varying phenotypes despite identical genotypes -the different manifestations of the same genotype across the population if expressivity is CONSTANT: all individuals with a given genotype express the same phenotype if expresivity VARIABLE: individuals with same gneotype may have different phenotypes
how does the cardiovascular system affect blood pressure via the kidneys?
vasoconstricting or vasodilating -constriction of afferent arteriole will lead to lower pressure of blood reaching glomeruli (adjacent to juxtaglomerular cells) -so vasoconstriction will secondarily lead to renin release to help raise BP
How is the transfer of thermal energy (heat) regulated via body surfaces?
vasodilation and vasoconstriction -nasal and tracheal cap mose frequently used for this 9 human spredom use sweating and shivering) (humans can and dogs ususally do use panting, transfer of heat to enviro through evaporation of water in muscous secretions)
How much of a role does adrenal testosterone play in male physiology?
very small since testes secrete large amounts
How do the microtubules coming from the centrioles attach to the chromosomes?
via kinetochores
What besides nutrients does the small intestine absorb?
water -water produced in secretions -up to 7 L per day taken back up -to maintain proper fluid levels, fluid is reabsorbed by OSMOSIS -solutes are absorbed directly into the bloodstream, wather is drawn with them, eventually reaching the capillaries water passes TRANSCELLULARLY (across cell membrane) and PARACELLULARLY (squeezing between cells) to reach blood
what is the primary purpose of the large intestine?
water absorption -large diameter, short length
When is aldosterone secreted?
when BP decreases -steroid hormone that is secreted by adrenal cortex
When are macrophages activated?
when a bacterial invader enters a tissue
when is insulin secreted?
when blood glucose levels are high -induces muscle/liver cells to take up glucose and store it for later use -stims anabolic processes like fat/protein synth
inbreeding depression
when individuals with similar genotypes - typically relatives - breed with each other and produce offspring that have an impaired ability to survive and reproduce -loss of genetic variation
When do the Na voltage gates close?
when mV approaches +35 mV...Na channels INACTIVATED -brought back to resting potential to become DEinactivated 3 states 1. CLOSED: before threshold reached 2. OPEN (threshold approx +35mV) 3. INACTIVE: from +35mV to Resting Potential
fat layer just below skin?
white fat, helps insulate body brown fat also may be present in infants(less efficient in ETC, so more heat energy released as fuel burned
how are the lacunae interconnected?
with tiny channels called canaliculi that allow for exchange of nutrients and wastes between osteocytes and the 2 types of cannals
Can axons be bundled together in the CNS?
yes, forms TRACTS -tracts only carry 1 type info -cell bodies of neurons in same tract grouped into one NUCLEI
Are females affected by disorders of the cortical sex hormone production?
yes, the ovaries secrete smaller amounts of androgens, so they are more sensitive to disorders