2nd Test Material Flashcards

Question

What do hormones bind to?

Answer 1

Specific receptors on target cells

Answer 2

Specifity; but some can bind to non-specific receptors

Answer 3

Replaced to maintain signalling

Answer 4

Plasma membrane of target cells

Answer 5

Dissolved in plasma; attached to membrane

Answer 6

in cell; bound to carrier proteins

Answer 7

Extracellular domain of the receptor and activates one or more cytoplasmic signalling pathway

Answer 8

phosporylation and enzyme activation

Answer 9

Adenylate cyclase pathway: 1. Hormone+receptor, G-proteins dissociate 2. alpha subunit activates AC 3. Catalyzes product of cAMP (ATP to cAMP) 4. Removes regulatory unit from PK (PKA) 5. PK activates other molecules (hormonal response) Epinephrine & adenylate cyclase: 1. Epinephrine binds to beta- adrenergic receptor on liver cell 2. G-proteins activated- subunit carrying GDP dissociates, GDP to GTP 3. Subunit activates adenylyl cyclase which catalyzes ATP into cAMP 4. cAMP activtes PKA, which activates phosphorylase 5. Phosphorylase converts glycogen to glucose-6-phosphate 6. Glucose-6-phosphate into glucose (released from liver)

Answer 10

- Recieved the 2012 Nobel prize in chemistry - How the billions of cells in our body sense their environments - Focus on G protein-coupled receptors (proteins that reach through cell walls) - Understanding how these proteins work has been crucial to unravelling the complex network of signalling between cells

Answer 11

Phospholipase C-Ca2+ pathways: 1. Hormone + receptor, G-proteins dissociate 2. Activates PLC (photolipase C) 3. Causes breakdown of membrane phospholipid to IP3 4. IP3 binds to endoplasmic reticulum 5. Release of stored Ca2+ into cytoplasm 6. Ca2+ activates other molecules (hormonal response) Steroid hormone receptors: 1. Steroid hormone (eg estrogen, androgen) transported bound to plasma carrier protein - Lipophillic (ie they move across plasma membrane) 2. Steroid hormone binds cell cytoplasm receptor 3. Translocates to the nucleus, binds to DNA - acts as transcription factor 4. Stimulates gene transcription 5. Protein products 6. Response basically steroid hormones travel in blood bound to carrier proteins, being lipophilic, they pass through cell membrane, in the cell, they bind to cytoplasmic receptors, the receptor-hormone complex moves into nucleus and binds DNA, activates gene transcription, leading to protein production, initiates cellular response Thyroid receptors: 1. Thyroxine (T4)+carrier binding protein 2. T4 into T3 (triiodothyronine) 3. T3 uses binding proteins to enter nucleus 4. Hormone receptor complex binds DNA 5. New mRNA 6. Protein 7. Response

Answer 12

phospholipase C (via Gq) (PLC)

Answer 13

Adenylate cyclase (via Gs)

Answer 14

G(s) alpha, G(a) alpha etc

Answer 15

Hypothalmic neuroendocrine cells (hormone 1; blood vessels) Anterior pituitary cells (hormone 2; general circulation) Splits into target tissues (endocrine and non-endocrine) (goes into general circulation) Ellicits a tissue response Summary: goes from hypothalamus to anteriior pituitary, release hormone to peripheral targets to ellicit effects

Answer 16

connected to hypothalamus through infundibulum (stalk)

Answer 17

Endocrine gland (one above and on left)

Answer 18

Extension of neural tissue

Answer 19

Makes up lobe of anterior pituitary

Answer 20

Tissue that wraps around infundibulum

Answer 21

group of tissues between the anterior and posterior lobe (only exists in fetus) in fetus all 3, in adults only two the distalis and the tuberalis

Answer 22

Anterior pituitary

Answer 23

Pars nervosa and infundibular stalk

Answer 24

Contact with infidibulum or stalk

Answer 25

Connected only to blood vessels

Answer 26

- Dopamine - Prolactin releasing hormone (PRH) -Thyrotropin-releasing hormone (TRH) -Corticotropin-releasing hormone (CRH) -Somatostatin (GHIH) - Growth hormones releasing hormone (GHRH) - Gonadotrophin-releasing hormone (GnRH)

Answer 27

Inhibits secretion of prolactin, also called that since prolactin inhibiting hormone

Answer 28

Stimulates release of prolactin

Answer 29

Regulates secretion of thyroid stimulating hormone (TSH)

Answer 30

Regulates secretion of adrencoticotrophic hormone (ACTH)

Answer 31

Inhibits secretion of growth hormone (GH), also called this since growth hormone inhibiting hormone

Answer 32

Stimulates secretion of GH

Answer 33

Regulates secretion of gonadotrophin-relasing hormones, lutenizing hormones (LH), and follicle stimulating hormones (FSH)

Answer 34

IH means inhibiting hormone and RH is releasing hormone

Answer 35

Stress axis

Answer 36

1. When body is stressed, neurosecretory cells of hypothalamus are going to release CRH (corticoidtropin releasing hormone) 2. Stimulate anterior pituitary in network of blood vessels to stimulate anterior pituiatary to secrete ACTH or adrenocorticotrophic hormone 3. ACTH travels through circulation to the adrenal cortex of the adrenal glands which is on top of the kidney which stimulates cortex of adrenal gland to secrete increasing amount of glucocorticoids (cortisol) - proceeds with catabolism (break down of proteins, stimulate liver to make amino acids to glucose)

Answer 37

Rise of blood glucose levels; causes stress which causes breakdown of fats and muscle which allows glucose in the blood for quick energy

Answer 38

Body is very stressed during exams, lots of cortisol, supressing your immune system saving energy for stressful times

Answer 39

Negative, once reaction has subsided, cortisol is going to feed back to anterior pituitary as well as hypothalamus to stop CRH and ACTH

Answer 40

Increase in ACTH or otherwise known as POMC (proopiomelanocortin) which increases levels of ACTH, POMC is a pro hormone

Answer 41

Corticotropin releasing hormone (from hypothalamus)

Answer 42

Adrenocorticotoropic hormone (from anterior pituitary)

Answer 43

Glucocorticoid, chronic stress hormone

Answer 44

From parvocellular neuroendocrine cells within the nucleis of hypothalmus (hypothalamic paraventricular nucleus)

Answer 45

Stimulation (activation): - Noradrenaline triggers CRH production - Stimulates pre-proCRH genes and protein (precursour) (196 AA) - Processed into CRH (41 AA) - Released in pulses Inhibition (suppression) - Cortisol (stress hormone) block CRH release and may reduce gene expression; may stop both CRH and proCRH expression

Answer 46

At median eminence (base of brain) from neurosecretory nerve terminals, into blood vessels in the hypothalamic-pituitary portal system

Answer 47

Carry CRH peptides to anterior lobe of pituitary where they stimulate cortiocotropes to secrete adrenocorticotropic hormone (ACTH)

Answer 48

Adrenocorticotropic hormone (regulates adrenal cortex function)

Answer 49

Melanocyte stimulation hormone (skin pigmentation in response to UV radiation)

Answer 50

beta endorphin (analgesic roles in central nervous system)

Answer 51

enkephalin (analgesic roles in fetus)

Answer 52

receptors in hypothermia, hypotension, feeding behaviour, appetite)

Answer 53

Cleave at certain areas to get different proteins to help in these processes (only ACTH for now)

Answer 54

2 distinct tissues that merged during development (similar to pituitary) Have adrenal cortex: secretes steroids (corticosteroids) 3 types of corticosteroids 1. Glucocorticoids (eg cortisol): controlled by ACTH (glucose for energy stress) 2. Mineralocoritcoids (eg aldosterone): controlled by renin-angiotensin system (sodium and potassium balance) 3. Sex steroids (eg testosterone): controlled by ACTH Adrenal medulla: modified sympathetic ganlia, secretes catecholamine (eg epinephrine)

Answer 55

Mineralocorticoids (cortex of adrenal)

Answer 56

Glucocoritcoids (cortex of adrenal)

Answer 57

Androgens (cortex of adrenal)

Answer 58

Epinephrine

Answer 59

Corticosterone

Answer 60

1. Promotes against hypoglycaemia (low blood sugar) 2. Promotes gluconeogenesis (increase blood sugar) 3. Plays a role in immune system - supresses immune system - regulates inflamatory responses (glucocorticoids used clinically as anti-inflammatory agents) - Causes breakdown of skeletal muscle for gluconeogenesis - Causes bone catabolism - Affects brain function (mood, memory, learning)

Answer 61

Causes Cushings Syndrome (primary hypercortisolism) - Can be causes by taking glucocorticoid drugs, or diseases that result in excess cortisol, ACTH or CRH - Causes changes in carb and protein metabolism, hyperglycemias, hypertension, muscle weakness - Metabolic problems gives rise to puffy appearance, CNS disorders (depression, decreased learning and memory etc)

Answer 62

- Pituitary dependent ie tumour in pituitary gland makes large amounts of ACTH, causing adrenals to make excess cortisol other one syndrome has lower ACTH

Answer 63

- Surgically remove pituitary or adrenal gland - Medical management of signs and symptoms (eg insulin for diabetes, anti-hypertensives for BP, etc) - If not treated, disease worsens, overall health can deteriorate (especially worsening diabetes and high BP which can lead to stroke or MI) myocardial infarction)

Answer 64

Addisons Disease (primary hypocortisolism) - Adrenal insuffiency - Many causes (genetic, autoimmune destrcution of adrenal cortex, etc) - Can be acquired due to high dose steroids given for over 1 week (supresses CRH and ACTH wheich suppresses adrenal glands) - Symptoms include hair loss, blurry vision, abdominal pain, darkening of skin, tremous, depression

Answer 65

Continuous, pulsatile, circadian release

Answer 66

Wake up peaks, before bed goes down

Answer 67

In older horses but has been diagnosed as young as 10 years Cause: - Impaired pituitary (hyperplasia and hypertrophy of pars intermedia middle part of anterior pituitary) - Leads to increased secretion of cortisol by adrenal glands - Results in high blood glucose and supression of immune system What are signs? - Hypertrichosis (excesive hair growth) - Abnormal hair coat including patches of long hair on legs, wavy hair on neck, and changes in coat colour - Muscle atrophy - Excessive sweating - Formation of fat pads on top of neck, tail head and above/around eyes - Pot-bellied appearance

Answer 68

- Measuring resting (basal) ACTH and fasting insulin Treatment: meds - Acts on pituitary gland to decrease circulating ACTH ex. pergolide Treatment- management - Excercise - Weight loss (if obese) - Limit starch/sugar in diet

Answer 69

1. Hypothalamus releases thyrotropin-releasing hormone 2. Down vascular system to anterior pituitary stimulate anterior pituitary to release the thyroid-stimulating hormone 3. Travel down to thyroid gland stimualte secretion of thyroid hormones T3 and T4 (thyroxine) Balanced by negative feedback through thyroxine

Answer 70

Just below the larynx (ie voice box) - on either side of the trachea (lateral to the first 3-8 tracheal rings) 2 lobes are connected by isthmus - Very fibrous in cows and horses - Almost impossible to find in dogs and cats - Largest purely endocrine gland (20-25g)

Answer 71

- Follicles that take up iodide from the blood - In colloid (fluid surrounding follicles) thyroid peroxidase enzyme (TPO) helps attach iodide to tyrosine residue in thyroglobulin

Answer 72

Made by folliular cells - Long peptide chain with lots of tyrosine side chains - Found in colloids - Iodide brough from blood into folliuclar cells by sodium-iodide transporter, then into colloid by transporter called pendrin - TPO (thyroid peroxidase enzyme) removes electron from iodide to produce iodine

Answer 73

- Attachment of 1 iodine on tyrosine ring make MIT (monoiodotyrosine) - Attach,ent of 2 iodines on tyrosine ring makes DIT (diiodotyrosine) - Enzymes on colloid modify the strucutres of MIT and DIT, joining them together - Triiodothyroning T3 (MIT+DIT) - Tetraiodothyronine T4 (DIT+DIT)

Answer 74

Yes, then thyorgloulin taken back up by follicular cells and cut, seperating T3 and T4, upon stimulation by TSH - T3 and T4 secreted out to bloodstream (bound to carrier protein) LIPID LOVING need carrier proteins

Answer 75

must get converted to T3 once in target cells cytoplasm, needs one T3 in nucleus and vitamin a derivative both binds to tre (hormone response element in nucleus) make protein and response

Answer 76

- Pulse secretion of from hypothalamus - Young animals secrete more then older animals - Stress and cold result in increased secretion - Secretion highest in humans between 10 am and 2pm - Thyroid horomones elevate basal metabolic rate (ie resting rate of caloric expenditure by body) - Secretion highest in rodents at night instead of day

Answer 77

- Elevated basal metabolic rate - Needed for normal gonadal development and function - Needed for normal embryonic/fetal development, particularly for developement of CNS - Production often impaired with age - Deficiency or excess may have bad consequences

Answer 78

Hypo: - Low basal metaoblic rate - Weight gain, lethargy, intolerance to cold Hyper: - Increase metabolic rate - Weight loss, muscular weakness, nervousness, protruding eyes

Answer 79

- Insuffucient dietary iodide - Thyroid gland defect - Impaired thyroid hormone pathway - Insiffuence TSH from anterior pituitary - Insufficient TRH from hypothalamius - Mutant TSH or TRH receptors (genetic) - Mutant TH transport proteins - Autoimmunity

Answer 80

- Deficiency of thyroid hormones - Usually due to innate maternal hypothyroidism, but also from iodine deficiency - Diet defificent in iodine affects many worldwide - Reduced physdical growth and developmental delays - Treatment with thyroxin T4 soon after birth (especially before 1 month of age), completely or almost completely restores mental developmeny by age 5

Answer 81

In utero and is completed after birth - Important for dendritic and axonal growth, myeling formationm and synapse formation - Important for neural migration - Maternal thyroid homrones first supply the needs of the embryo/fetus

Answer 82

Abnormal tyroid growth due to hypothyrodism 1. Low iodide intake reuslts in low thyroid hormone production 2. Low plamsa thyroid hormones results in high TRH 3. High TRH results in high plasms TSH 4. High plasma TSH stimulates excess growth of thyroid Since low thyroid hormones t4 leads to negative feedback loop not working causing it to overproduce

Answer 83

Hyperthyoridism - Autoimmune antibodies activate thyorid gland, lkeading to high T3 and T4 - High thyroid concentration leads to low TRH and low TSH - Causes protruding eyes

Answer 84

No, since diff from patient to patient

Answer 85

- Weight loss - Increased thirst - Increase urination - Increased heart rate - Vomting and diarrhea - Restlsness and hyperactivity - Greasy or matted hair

Answer 86

Primary hypothyrodism (destruction of thyroid) 1. Lymphocytic thyroditis (immune filtration); affect 50% doberman pinschers 2. Idiopathic atrophy of thyroid (thyroid tissue lost and replaced by adipose cells)

Answer 87

1. thyroid destruction secondary to neoplasia; affects 40% of dogs with cancer (thyroid cancer) 2. Congenital hypothyrodism/crenitism/pituitary dwarfism (conginetal issues) more then 75% of both lobes must be non-functional before developing clinical signs (75% of thyroid must stop working before symptoms appear ex. myxedema (tissue swelling, stupor, coma)

Answer 88

1. Surgery (eg hemithyroidectomy) 2. Hormone supplementation (start with low dose) 3. Radiation therapy (cancer) 4. Blockers (eg thiouracil derivatives and thiocarbamides decrease iodiantion and conversion from t4 to t3) 5. Stimulants (eg furosemide increases conversion from t4 to t3) 6. Diet, electrolyte infusions, etc`

Answer 89

99%; stored as hydroxyapatite - Made up of calcium salts and phosphate which allow for structural integrity making them strong

Answer 90

In soft tissues; intracellular (0.9%) and extracellular (0.1%) calciu ions essential for several normal biochemical processes (neuromuscular excitation, blood coagulation, hormone secretion, enzyme acitivty, fertilization etc)

Answer 91

Intracellular (0.9%): - Highly regulated - More abundant - Assoscioated with membranes in mitochondria, ER and plasms membrane Extracellular (0.1%): - Tightly regulated - about 50% ionized (free) - 40% protein bound - 10% complexed with phospahte and citrate

Answer 92

intake-output

Answer 93

Intake=diet - 1/3 absorbed in small intestine - Absoprtion is hormone regulated - Recommeneded about 1000mg/day Output=kidneys - Body cany make it so has to be replaced

Answer 94

1. Parathyroid hormone (PTH) 2. Calcitriol (vitamin D3) 3. Calcitonin 1 and 2 most important for adults

Answer 95

- PTH is a peptide made by parathyroid gland - PTH is secreted continously (not stored) - PTH helps regulate calcium - Thyroid gland can be surgically removed, but parathyroid gland cannot (needed for life) - Parathyroids seen in terrestrial amphibians onwards first appeared with them and now found in higher animals

Answer 96

1. Chief cells (produce PTH) 2. Oxyphils (function not known) larger

Answer 97

PTH acts to raise blood Ca2+ back to normal via 3 mechanisms... 1. Stimulates osteoclasts to resrob bone (primary mechanism) 2. Stimulates kidney to resorb Ca2+, (tells kidneys to keep more Ca2+ instead of excreting it) 3. Stimulates kidneys to produce enzyme needed to activate vitamin D, which promotes better absorption of Ca2+ from food/drink across intestinal epilethium (activating vitamin D to help absorb more Ca2+ from food)

Answer 98

- Vitamin D3 -PTH Parathyroid

Answer 99

- Calcitonin and thyroid

Answer 100

Hypo: increases PTH secretion (stimulates resorption to get more Ca2+ back into blood) Hyper: decreases secretion

Answer 101

Bone resporbption: - Osteoclasts dissolve hydroxyapatite and return the bone Ca2+ (& phosphate) to the blood Bone deposition: - Osteoblasts secrete a matrix of collagen protein, which becomes hardened by deposite of hydroxyapetite

Answer 102

Stimulates kidneys to reabsorb Ca2+ and produce 1-alpha-hydroxylase enzyme needed to activate vitamin D, vitamin D3 will act on intestine to absorb more Ca2+ fro food/drink

Answer 103

1. Vitamin D3 produced from its precurcor molecules 7-dehydrocholesterol under the influence of UVB sunlight (vitamin D3 comes from 7..., uvb sunlight converts it into previtamin D3, which then becomes vitamin d3) 2. Vitamin D3 secreted into blood from skin/intestine (functions as pre hormone ie inactive) (vitamin d3 enters blood but inactive, transported from skin and intestines into the bloodstream) MUST BE ACTIVATDED BY LIVER AND KIDNEYS 3. Goes to liver and is chemically changed (hydroxyl group added to C25) 4. Requires hydroxyl group addition to C1 to become active (done by enzyme in kidneys stimulated by PTH)

Answer 104

- Stimulates intestinal absoprtion of Ca2+ - Directly stimulates bone resorption by promting promoting formation of osteoclasts

Answer 105

Humans: synthesized by 7-dehydrocholsterol with uv light in skin and obtained from dietary sources Dogs and cats: obtained only from diet

Answer 106

food sources (fortitifed milk, eggs, fish) provide on average only 10-20%

Answer 107

- Made in C cells of thyroid in response to high Ca2+ - Thought to play a minor role in adult humans (thyroidectomy patients are not hypercalcaemic)

Answer 108

Yes, but not as stirictly, it moves between the bones, kidneys and digestive tract to maintain balance

Answer 109

Hyper: - Parathyroid to active - Hypercalcaemia (too much Ca2+) - Increased bone resoprtion (fractures) - Mineralization of soft tissues - Increased thirst and urination (Ca2+ blocks ADH antidiaretic hormone effects) - ADH helps kidneys retain water and produce concentrated urine Blocks ADH from keeping it so releases it Hypo: - Parathyroid not active enough - Hypocalcaemia not enough Ca2+ in blood - Musuclar weakness, ataxia - Cardiac arrythmias

Answer 110

- Poor bone mineralization Children=rickets - bone pain, stunted growth, deformities In adults=osteromalacia - Bone pain, fractures - Soft bones

Answer 111

- Most common disorder of the bone - Reduction of bone quality due to excess absoprtion - Risk of bone fractures Known risk factors: - Sex (females, especially after menopause) - Lack of excercise - Calcium deificient diet BONE BREAKDOWN

Answer 112

Women: 1 in 3 Men: 1 in 5

Answer 113

- Adequate calcium and vitamin D intake - Hormone therapy, PTH, calcitonin (may be associated with cardiovascular disease, stroke, cancer) - Excercise - Best treatment is prevention - Calcitonin reduces calcium levels by reducing bone breakdown

Answer 114

Regulates the growth hormone secretion

Answer 115

GH secretion inhibited by somatostatin from hypothalamus, GHRH stimulates secretion from anterior pituitary, GH has many targets (direct or through stimulation of liver's production of somatomedins (IGF-1) indirectly to produce somatomedins with growth and repair

Answer 116

Growth hormone

Answer 117

Protein (191 AA polypeptide) with a half life of 6-20 mins

Answer 118

Synthesized, stored, and secreted by lateral wings of the anterior pituitary gland

Answer 119

Binding protein (GHBP) but may be transported as free hormone, it is the most abundant anterior pituitary hormone, plays important role in growth

Answer 120

- Several, large, 10-30 min pulses/peaks each day (gh released in pulses throughout the day, each lasting 10-30 mins) - Biggest GH peak occurs about 1 hour after you fall asleep (linked to bodys circadian rhythm) - GH levels are highest in childhood and puberty, helping with growth - As you get olfer, GH levels decrease (called somatopause) - GH is why kids often wale up with sore legs, helps bones and muscles grow, sometimes causing discomfort

Answer 121

GH acts on liver to produce IGFs (insulin like growth factors) (IGF-1, IGF-2) - Polypeptides with 40% homology to insulin - IGF-1 mostly travels in blood almost entirely bound to transport proteins (IGF-BPs) - Some IGF-1 transport/binding proteins have an endocrine function (ie there are receptors for these proteins) - GH stimulates the synthesis/release of IGF-1 in other tissues besdies the liver ie difficult to differentiate between direct actions of GH and IGF-1 - GH and IGF-1 appear to exert oppsotie actions in some tissues, suggesting independent roles

Answer 122

Yes!; GH does opposite (IGF-1 helps cells use sugar better)

Answer 123

1. Liver to release IGF-1, which increases bone and cartilage growth, promotes protein synthesis and growth 2. Adipose tissue: increases fat breakdown and releasing fatty acids for energy 3. Most tissues, reduces glucose meaning bodies relies more on fats for energy

Answer 124

In children; children have 2 periods of rapid growth: postnatal and puberty - GH stimulates growth of 1. Bone and cartilage 2. Soft tissue - Hypertrophy: increased cell size (size of trophy) - Hyperplasisa: increase cell number

Answer 125

Bone diameter increase - Growth occuring around the bone - Matrix deposits on outer surface of bone Bone length increase - Growth occuring at epiphyseal plates (near ends of bones) - Epiphyseal plate coontains chondrocytes (columns of collagen-producing cells) - As collagen layer thickens, old cartilage calcififes and chondrocytes dengenerate - Osteoblasts invade and lay bone matrix on top of cartilage base Summary for bone length increase: - Happens at epiphyseal plates (growth plates) near the ends of bones - Chondocytes (cartilage cells) make collagen to help bone grow - Over time old cartilage hardens (calcifies) and chondrocytes die - Osteblasts (bone building cells) replace cartilage with new bone matrix

Answer 126

YES! GH stimulates production of IGF-1 in liver, IGF-1 helps stimulate chondrocyte and osteoblast acitivty

Answer 127

in growing animals, GH underproduction/decreased sensitivity; small size, juvenile proportions, normal shape but stunted

Answer 128

In growing animals, (laron type dwarfism) decreased responsiveness to GH (receptor deficiency)

Answer 129

In adult animals; thin skin, hair loss (poodles)

Answer 130

Adult animals; increased cortisol inhibits GH synthesis

Answer 131

In growing animals

Answer 132

In adult animals; thinking of bones/ joints and skin, enlargement of internal organs (tongue, liver, spleen)

Answer 133

Severe GH or GHR deficinecy in children

Answer 134

Over secretion of GH in children

Answer 135

Over secretion of GH in adults, lengthened jaw, coarse faical features, groeth of hands and feet

Answer 136

- Wrestler and actor - Gigantism, acrogmegaly - 7'4 - DIed at age 47

Answer 137

- Approved by US FDA 2003 to treat children with short stature - Daily injections for about 2 years increased height by 1.3 inches - 22,000/year cost - Glucose intolderance, pancreatitis, and psycholgoical problems surroinding height

Answer 138

- Maintaining msucles mass for those with AIDS - Bodybuilding

Answer 139

Selective breeding

Answer 140

- Munchkin genetci mutation - Chondrodsyplasia, short-legged

Answer 141

- Dwarf breed, normally proportioned - Severe delay in growth msy cause bone, muscle and other endocrine problems

Answer 142

GH deficiency, smal body - Most toy breeds little

Answer 143

Shortened skull bones - Flat face short muzzle (eg boxers)

Answer 144

- Short legs - basset hounds, bulldogs, corgis, daschunds, socttish terriers, shetland sheepdogs

Answer 145

Maybe slows it, but scientific evidence is weak, many GH products dont work as advertised GH broken down in tummy

Answer 146

Cattle treated with synthetic GH (growth hormone) - 30% increase in milk - Faster growth - Leaner meat (marbling less fat) - Adverse effects on reproduction? - Adverse effects on humans eating it? - Legal in the USA, illegal in Canada

Answer 147

- Large protein that acts as a precursour molecule - Gets cut by enzymes called converses to produce functinoal peptisades in the body 1. POMC (parent molecule) - 130 amino acids gets broken down into smaller peptides 2. Key products from POMC cleavage: - ACTH (adrenocorticotropic hormone): stimulates cortisol release from adrenal glands - gamma msh involved in skin pigmentation - alpha msh affects skin colour and appetite regulation - beta msh similar function to alpha - CLIP (corticotropin-like intermediate peptide) function not well understoof - gamma LPH (lipotropin): endorphins, involved in fat metabolism - Enk (enkephalin): pain regulation (acts like opiods)

Answer 148

Cleave POMC; different convertases gives rise to different products

Answer 149

13: Main hormones: 4 postranslational peptides - Melanocyte-stimulating hormones (alpha-MSH, beta-MSH, gamma-MSH) - Adrenocorticotropic hormone (ACTH) 5 Melanocortin receptors: 7 membrane; G-coupled protein receptors - MC1R, MC2R, MC3R, MC4R, MC5R 2 melanocortin antagonists - Agouti, agouti related protein (AGRP) 2 proteins that modulate melanocortin activity - Mahogany, syndican-3 1 opiod peptide (product of POMC but not part of melanocortin system) - beta endorphin (pituitary, blocks pain) DIFF ROLES THEN REST

Answer 150

Yes, different parts of the body process POMC differently to create different hormones Different cell types make different POMC products - Example; pituitary gland makes ACTH, while while skin produces MSH for pigmentation - One prohormone (POMC) can create multiple hormones that control various body functions (stress, appetite, pain, skin colour) - MUTATIONS IN POMC IS RARE BUT POSSIBLE, which can lead to obesity or pigmentation disorders

Answer 151

Reduces hunger; if mutated can cause early diabetes

Answer 152

Affects pigmentation, works on melanocytes (cells that produce melanin); if mutated can ause skin colour changes (eg diff pigmentation in humans or coat colour in animals)

Answer 153

Produced in adrenals, skin, brain, penic etc; penile MCR mutation associated with sexual function/dysfunction

Answer 154

Yes... - Alpha MSH binds to MC1R - Activates signal pathways (G-protein coupled receptors, cAMP, pKA, CREB) - Synthesis of MITF (microphthalmia-associated TF) - Transcription of Tyr and DCT which influence pigmentation

Answer 155

- Mutation discovered in 1905 - Mutated gene results in overproduction of Agouti protein - Agouti protein is antagonist to MCR1 in skin - Results in yellow pigmentation - Agouti protein antagonist to MCR4 in brain - Overeating and obesity - Model for obesity, hyperglacaemia, and insulin resistance

Answer 156

6% have condition known as melanism (dominant gene mutation in MC1R) making black

Answer 157

2 copies of recessive mutation in MC1R protein

Answer 158

- Linked to MC4R mutations - Alpha msh analogs used to treat erectile dsyfunction - Eg melanotan II - Binds to MC3R and MC4R in the brain to increase sexual function

Answer 159

each gland has 7-10 lobes divided by adipose tissue (fat tissue) - each lobe is made up of smaller lobules

Answer 160

Alveoli; which make milk - milk goes from alveoli to small tubes (secondary tubles) to larger ducts (mammary ducts) to lactiferous duct to nipple - milk collects in lumen of duct during nursing

Answer 161

- Placenta secretes estrogen and progesterone which stimulates growth and development of mammary gland, after birth estrogen sectretion decreases, and prolcatin secretion increases; milk productin under control of anterior pituitary - Milk release under control of oxytocin from posterior pituitary

Answer 162

- Proteins (casein, lactalbumin) - Lipids - Carbs (primarily lactose) - Vitamin A, B, D, E - Caclium, iron, zinc, selenium, etc - Immuniglobulin A (IgA) - Hormones, growth factors, chemokines

Answer 163

- Sex determining region of the Y, found on y chromosome in all animals - It triggers male development by turning embryonic gonads into testes - If no SRY, ovaries develop instead

Answer 164

- Bipotential primordium (undifferentiated) - no gender yet

Answer 165

- Absense of SRY protein" gonadal tissues develops into ovaries - Absence of testosterone and Sertoli cells, means no MIF, wolffian duct degenerates but mullerian duct presence maintained - Absence of MIF, mullerian duct becomes fallopian tube, uterus and vagina

Answer 166

- presence of sry protein, gonadal tissue develops into testes - presence of testerone, mullerian inhibition factor (IMF) made from sertoli cells - MIF means wolfian duct maintained, mullerian duct degenerates - Testosterone causes Wolffian duct to become seminal vesicle, vas deferens, and epididymis

Answer 167

Both have genital tubercle, urethra folds, urogenital sinus, and labioscrotal swellings

Answer 168

Mascunalize the structures... Genital tubercle=penis Urethra folds=penil urethra Labioscrotal swellings= scrotum and prostate

Answer 169

Gential tubercle= clitoris Labioscrotal swellings= labia

Answer 170

46 CHS diploid (22 homologous pairs of autsomes and 1 pair of sex CHS) - Oocytes and sperm each contain half a set (23) chs (haploid) - zygote has unique set of 46 CHS- 1 of each homolgous pair from mother and 1 from father

Answer 171

XX male (with SRY on X) XY female (no SRY)

Answer 172

1992 olymic games: - gender verification-atheletes with sry gene not permitted to particiapte as females 1996 Olympic - females with sry gene rules as false positive and permitted to particiapte Late 1990s - call for elimination of gender verification due to ineffectiveness and uncertainty of method - supported by american medical association... 2000 olympic - screening eliminated but controversies continue

Answer 173

Yes three important receptors... 1. Insulin receptor (INSR) 2. Insulin-like growth factor 1 receptor (IGF1R) 3. Insulin receptor related receptor (INSSR)

Answer 174

Prevents testes, instead ovaries develop

Answer 175

Condition where a person has two or more different types of cells with different sex chromosomes in their body - ex some cells may have XX, while others have XY or just X - happens 1.5 out of 10,000 births - Spectrum ranges from: - turner sydrome (female with X)

Answer 176

- Have both ovary and testes - Various potential karyotypes - Various degrees of mosaicism - About 1 in 1500-2000 births (0.07-0.05% of children born with atypical genitalia requiring a specialist in sex differentiation

Answer 177

Where has external genitalia of one sex but internal organs of other sex - Ex males with a defective 5 alpha reductase gene - Enzyme that turns testosterone into DHT stronger form of test - Without enough DHT male genitalia doesnt fully develop - Baby looks female, but has teste inside at puberty test increases body starts developing male traits (deeper voice, male gential growth, facial hair)

Answer 178

- Germany, 2013 - Germany was first country in europe to allow babies with intersex traitd to be registered as neither male nor female at birth - Parents could leave gender blank on birth certificates, creating a new category called intermediate sex - Why to reduce pressure on parents to decide a babys gender - To avoid unnecessary gender assignment surgeries on newborns Criticism of law - some felt it dindt go far enough since 1 in 2000 people are born with intersex traits (didint do enough to protect them)

Answer 179

Australia (2011) and New Zealand (2012): people can choose x instead of female or male on passports Bangladesh (2011): added other gender option for passports Nepal (2007): added a third gender option on census forms Pakistan (2011): added third gender option on national id cards India (2009): added a third gender category on voter list Thailand: intersex and transgedner people accepted and even recognized by military - do not have seperate legal status no speical legal protections

Answer 180

- in 2016 provinval government of ontario changes to way gender is displayed on health cards and drivers licenses - ontario health card no longer displays sex designation - early 2017, ontario drivers license to option to dosplay x as gender idenitifer on drivers licenses - 2018, ontario issued first non binary birth certificate to joshua m ferguson who stated new policy will save lives in trans community

Answer 181

- rapid growth and developwith with earlier more obvious signs in females

Answer 182

HPG axis resulting in gonadal maturation - Adolescence: maturation of adult social and cognitive behaviours - coupling of both through interactions of nervous system and gonadal steriod hormones

Answer 183

High at birth, remaining high for the first 6 motnhs of postnatal life before declining to low levels until puberty - Puberty triggered by increase of LH (not constant) - More pulses=puberty starts - LH secretion is higher at night then day Roles of other hormones: - GnRH (from brain) tells body to release more LH - LH triggers sex hormones production: - Test (boys) - Estrogen - Next more sex hormones= puberty changes

Answer 184

- Hormone that controls puberty and reproduction - Does release steadily, but in pulses Why is it important - triggers puberty, by telling body to release LH and FSH which stimulates test and estorgen If no GnRH do not go through puberty normally and may stay sexually immature How is GnRH used in treamtment? - Only works if given in pulses - steady gnrh wony work since body knows pulses

Answer 185

No! diff factors can speed up or delay when happens Genetics: some start ealsier or later based on family traits Environment= higher altitudes can delay it Nutrition: poor diet xan slow puberty, while good nutriton speed up Chronic illness some can delay Hormones and chemicals some people worry that synthetic homrones or environemntal chemicals affect puberty timing Precocious puberty: pubery starts really early age 8 girls and 9 boys

Answer 186

Formation and genetic/phenotypic maturation of gametes

Answer 187

- First phase is identical in males and females - Distinct differences in last 3 phases in males and females

Answer 188

1. Extraembryonic primordial germ cells (PGSs) and their migration to the gonads 2. Increase the number of PGCs by mitosis 3. Decrease in chromosomal material by meiosis (lose half their CHS) 4. Structural and functional maturation of gametes (oogenesis/spermatogenesis)

Answer 189

- Earliest precursor of gametes - Originate outside of the gonads in the hindhut - Migrate into the gonads during early embryonic development

Answer 190

- No recombination - Daughter cells are identical

Answer 191

- Recombo - Daugther cells have reduced ploidy

Answer 192

- Same CHS number - Inherited from each parent ie 1 paternal, 1 maternal - Allelic differences

Answer 193

- Same CHS - Replicated DNA (copies before division) - Exact copies of a chs before it splits

Answer 194

Diploid: 2 sets of homologous CHS (same CHS number, 1 maternal and 1 paternal) Haploid: 1 set of homologous CHS (1 copy of each number)

Answer 195

- Exchange of segments between 2 CHS during pachytene (third stage of prophase I in meiosis) stage - Not a purely random process - Occurs at hot spots located based on configurations of proteins that organize the CHS early in meiosis - Occurs within small region of homology between sex CHS (x and y) - Hypermethylation of histone proteins in chromatin indiates sepcific sites where DNA strands break and are repaired after crossing over is complete - Crossing over usually occurs in meiosis - Increases genetic diversity

Answer 196

- Holds sister chromatids together during division

Answer 197

- Important for chromosomal compaction - Needed for both mitosis and meiosis

Answer 198

Female: oocyte/egg/ovum Males: spermatozoon (sperm)

Answer 199

- Occurs in the testes - Indefinite process yielding 4 games per cycle - Process in which spermatozoa are produced by male primordial germ cells by mitosis and meiosis - Initial cells called spermatogonia (stem cells), which yield primary spermatocytes by mitosis

Answer 200

Seminiferous: tubes inside the testes where sperm is made Leydig: make testosterone Serology: support and nourish developing sperm Epididymis: stores and matures sperm before release

Answer 201

- Diploid stem cells that give rise to 2 daughter cells - One daughter cell reamins at the basement membrane as a stem cell - Second daughter cell (primary spermatocyte) moves towards the tuble lumen

Answer 202

1 meiosis: DNA duplicates and daughter cell splits into 2 new, haploid daughter cells (secondary spermatocytes) 2nd: duplicate chromatids split into 4 daughter cells (spermatids) primary spermatocyte undergoes 2 meitoic divisions to form 4 haploid spermatids

Answer 203

- From spermatogonium to primary and then secondary spermatocyte

Answer 204

- From secondary spermatocyte to spermatid

Answer 205

From spermatid to mature, immotile spermatozoon

Answer 206

From mature, immotile spermatozoon to mature, motile spermatozoon

Answer 207

- Results in formation of spermatocytes possessing half of the normal complement of genetic material Phase 1 (spermatogonial phase) - Type A dark (Ad): stem cells that stay in the testes - Type A pale (Ap): start developing into sperm - Type B: fully committed to becoming sperm Phase 2: - Each primary, diploid spermatocyte duplicates ints DNA and divdies into 2 haploid, secondary spermatocytes by meiosis I

Answer 208

- Creation of spermatids from secondary spermatocytes - Secondary spermatocytes rapidly enter meiosis II and divide to produce haploid spermatids - Brevity of this stage means that secondary spermatocytes are rarely seen in histological studies (stage is short!!!)

Answer 209

- Spermatids form tail by growing microtubles (axoneme) on one of the centrioles (basal body) - Anterior part of the tail (midpiece) thickens due to mitochondrial arranement (energy supply) - DNA undergoes condensation - Tightly packed chromatin is transcriptionally inactive - Golgi apparatus surrounds the condensed nucleus forming the acrosome (helps sperm penetrate egg) - Test removes remaining cytoplasm and organelles (resaudual bodies removed by sertoli cells) - Results in mature by immotile spermatozoa

Answer 210

1. Golgi phase - Small vesicles on the golgi fuse and form proacrosomic granules (stay located on one side of the nucleus) - Centrioles migrate to opposite side of the nucleus - Golgi vesicle fusion continues forming a large acrosomic vesicle with a dense acrosomic granule - PC forms attachment point of flagellum - DC gives rise to flagellum itself 2. Cap phase - Acrosomic vesicle forms caps over one side of nucleus (anterior portion) - Golgi and other cytoplasmic organelles migrate toward distal portion of cell - Flagellum start to form from distal centriole 3. Acrosomal phase - Nucelus beings to elongate - Microtubles are reorganized and form manchette - Neck and annulus form - Flagellum continues to develop 4. Maturation phase - Machette forms post nucelar cap - Mitochondria migrate to posterior side of nucleus and form spiral assembly which defines midpiece - Annulus forms connection between middle and prinicpal pieces of flagellum

Answer 211

Nucleus: holds compact DNA, shaped for easy movement - oval, flattened, compact, with condensed DNA (disulfide cross-linking; protamines) Acrosome: contains enzymes to help sperm penetrate the egg, membrane vessicles with multiple hydrolytic enzymes - covers the anterior 2/3 of the nucleus - enzymes used for acrosmomal reaction during fertilization Postnuclear cap: membrane component posterior to acrosome Plasms membrane: integrity needed for cell survival and function (protects it and keeps its functional)

Answer 212

Capitulum: neck that attaches flagellum to head Middle piece: mitochondria sheath in spiral (helix) assembly (high production of ATP) (has mitochondria to produce energy (ATP) for movement Principle piece: major piece of flagellum; important for movement Terminal piece: end of microtuble fibers Plasma membrane: covers all segments

Answer 213

- Release of mature spermatozoa from sertoli cells into the lumen of the seminiferous tuble - Mature, immotile speratozoa transported to the epididymis in testicular fluid secreted by sertoli cells with the aid of peristaltic contrations Summary: go from sertoli cells into lumen of seminiferous tuble, then to epididymis

Answer 214

About 1000-2000 stem cells; therefore meiosis is crucial to produce to produce sperm throughout adult life - Median ejaculation (50th percentile) contains about 255 million sperm in 1.5-5 millilitres of seminal fluid

Answer 215

low sperm count; less then 20 million sperm/ml - Lead to decreased fertility

Answer 216

Only able to surive for around 80 hours after ejaculation - Female cervical mucus helps to maintain metabolic requirements of spermatozoa - When migrating in genital tract, spermatozoa are seperting from seminal plasms, and resuspended in female genital fluid - Spermatozoa undergo capacitation during passage through female reproductive tract (become fully able to fertilize egg)

Answer 217

YES - most sperm eliminated at selective barriers (cervix and uterotubal junction) - Majority of sperm removed by phagocyotis - Damaged/immotile sperm carried back to cervix by ciliated cells (outside)

Answer 218

Structural and metabolic support - maintain environment and protect spermatids from immune system through: - Blood- testis barrier - FAS-ligand (binds to FAS-receptor on T cells, triggers apoptosis of T-cells, and prevents immune attack in developing sperm) -Phagocytose residual cytoplasm -Secrete: - Supporting testicular fluid - Substances that initiate meiosis - ABP (concentrates test in close proximity to developing gametes) (keeps test near sperm for development) - Hormones affecting pituitary gland in control of spermatogenesis (eg inhibin)

Answer 219

Seminterferous tubules Rete testis Efferent ductules Epididymis (head, body, tail) Ductus vas deferens Ejaculatory duct Urethra

Answer 220

1: sperm (supported by Sertoli cells) 2: test (leydig cells) darker like males

Answer 221

GnRH= gonadotropin releasing hormone secreted into portal vessels FSH= follicle stimulating hormone (gonadotropin) targets sertoli LH= luteinizing hormone (gonadotropin) targets leydig cells LL - Test will travel to other target cells, resulting in development of secondary sex characteristics

Answer 222

Negative feedback loop helps to maintain hormone levels to maintain balance 1. Test regulation: - hypothalamus releases GnRH triggerd anterior pituitary to relese FSH and LH - LH stimulates leydig cells to produce test - High test levels signal hypothalamus and anterior pituitary to reduce GnRH and LH production - Prevents excessive test levels 2. FSH regulation (via inhibin) - FSH stimulates sertoli cells to support sperm production - Sertoli cells also release inhibin which reduces FSH release from pituitary LH is NOT affected by inhiin so test production can still continue

Answer 223

they were castrated men who were used as royal servants since they were seen as less threatening - Castration was a punishment for sex offenders as early as 200 BC - 700 AD: testes extracts was used to treat impotence (erectile dysfunction) - 1869: watery testes extracts were beleived to boost maculinity (virtility) - 1935: scientists finally isolated test, understanding that it was the key male sex hormone

Answer 224

- Secreted by Leydig cells, located between seminiferous tubles (beginning of tract)

Answer 225

Masculinizes tract and external genitalia

Answer 226

- Growth, maturation, and maintenance of male reproductive system - Libido - Secondary sex characteristics (hair growth, voice, skin, body shape) - Bone, muscle - Brain (behaviour, cognition)

Answer 227

- Increased risk of infertility - Mimic the effects of test - Excess test shuts down pathway - Testes stop producing sperm - Testes stop producing test - Decreased libido and fertility

Answer 228

- Steriod users had less LH and FSH - Leading to reduced sperm production and lower natural test - After stopping steroids, hormone levels remianed low for 3-6 months - One year after stopping, hormone levels were similar to non-users, but sperm count took longer to recover - Steroid users often needed medical treatment to restore fertility

Answer 229

- Combo of progestin and an adrogen - When the injection was given every 6 months, some participants sperm production recovered earlier than expected - When given every 4 months, no escape meaning better supression of sperm production - First study to test this type of male contraception - Combo effecitvely supresses sperm production, is safe for the short term, and allows sperm production to return to normal after stopping the treatment

Answer 230

Flaccid (not errect): - Corpus cavernosum (spongy erectile tissue) not filled with blood - Blow flow minimal, and veins remain open, allowing blood to drain out Erect state: - corpus cavernosum fills with blood, causing penis to expand and harden - Arteries widen to increase blood flow, while veins get compressed, reducing blood drainage - Urethra is slightly compressed which helps with ejaculation

Answer 231

- Process that involves changes in blood flow and pressure

Answer 232

1. Parasympathetic nerves cause arterioles to widen by relaxing smooth muscle 2. Allows more blood to flow into the corpus cavernosum (spongy tissue inside the penis) 3. Veins contract, reducing bloodoutflow which helps maintain the ercetion 4.Increased pressure inside the corpus caernosum leads to erection -k Neurptransmitter nitric oxide

Answer 233

- NO released and activates enzyme (guanylate cyclase) in smooth muscle cells produces cGMP (singallng molecule) - cGMP lowers calcium (Ca2+) levels, causes smooth muscle cells to relax - Relaxed msucle cells allow blood vessels to widen (vasodilation) increasing blood flow and leading to penis errecton - Triggers msucle relxation, which increases blood flow and cases an erection

Answer 234

Sildenafil (Pfizer) - First tested on humans in 1991 - Was ineffective at first first treated to treat angina (chest pain) but didnt work - During trials patietns reported unexpected erections - Pfizer then tested it for erectile dsyfunction and it worked - Viagra became the first approved drug for erectile dsydunction in 1998 and still used today 7 years later ronaldo

Answer 235

- Blocks enzyme (PDE) that normally breals down cGMP (needed to stimulate erection) - cGMP helps relax smooth muscle, increasing blood flow - More cGMP means better muscle relaxtion, leading to erection

Answer 236

- Broad ligament - Ovaries - Oviducts - Uterus - Cervix - Vagina

Answer 237

- It is the folding of the peritoneum (mesothelium and connective tissue) Parts: 1. Mesoovarium (ovaries) 2. Mesosalpinx (oviducts) 3. Mesometrium (uterus, cervix) What is the function? - Supports hangs several anatomical components of reproductive tract (holds and supports reproductive organs) - Prevents friction - Houses vascular supply, lymphatics and nerves

Answer 238

- Glandular organs that house female gametes surrounded by ovarian follicles Anatomy: 1. Tunica albuginea (outer connective tissue) 2. Cortex (houses follicles and corpus luteum (hormones) 3. Medulla (houses vaculature, lymphatics and nerves) Function: 1. Production of oocytes (oogenesis) 2. Development of ovarian follicles (folliculogenesis) 3. Production of hormones (estradiol and progesterone)

Answer 239

Tubes connect the ovaries to uterus and help transport egg, sperm and embryos Infundibulum: captures egg after ovulation (fun time captures egg so much fun!) Ampulla: where fertilization happens Isthmus: help transport sperm and can store them Also called follopian tubes, uterine tubes or salpinges

Answer 240

- Hollow, pear shaped muscular organ in pelvic cavity Anatomy: 1. Endometrium 2. Myometrium 3. Perimetrium Function: 1. Site of embryo implantation and growth 2. Sperm transportation 3. Responsive to hormones (contractions) 4. Prostaglanding secretion (luteolysis) (drop in progesterone pp)

Answer 241

- Muscular tunnel-like organ located at lower, narrow end of uterus Anatomy: 1. Endocervix 2. Ectocervix (thicker) 3. Os 4. Cervical folds and crypts Function: - Barrier for uterine protection (safe from infections since at base) - Mucus production - Non-pregnant: lubrication and facilitate sperm motility - Pregnant: mucous plug seal pregnancy

Answer 242

- Elastic, muscular canal of 7-10 cm in legnth that serves as an entrance to female reproductive tract Anatomy: 1. Cranial region (secretes mucous) 2. Caudal region (protects) Function: - Copulatory organ (involved in sex reproduction, specifically in the transfer of sperm from male to female) - Birth canal - Mucus production for lubrication - Low pH (3.8-4.5)- micorenvironment regulation (microorganisms needed to prevent infection and sperm prevention (selection))

Answer 243

1. Provides anatomical closure to vagina 2. Minimize entry of foreign materials 3. Clitoris: highly erectile tissue, similar to penis - Corpus cavernosum (secrete mucous and relax with NO)

Answer 244

Gamete: egg Gonad: ovaries

Answer 245

hormones from the brain (hypothalamus and pituitary) and ovaries

Answer 246

Ovarian cycle: - Series of changes in ovary including follicle maturation, ovulation and corpus luteum formation= folliculogenesis Menstrual Cycle (uterine cycle) - Series of changes in hormone production and uterus structure that make pregnancy possible=uterine cycle

Answer 247

Supportive structure that secrete a variety or hormones - Made up of mutiple cell types that proliferate upon stimulation for HPG axis - Protect oocyte from environment, provide nutrition and biochemical support - Contribute to oocyte maturation - Folliculogenesis=follucilar phase of ovarian cycle

Answer 248

Primordial: single layer of flat cells surrounding oocyte, represent ovarian reserve (smallest, dormant) Primary: starts growing and developingl single layer of cubodial cells surrounding oocytes; makes estradiol (E2)!!! Secondary follicle: 2-3 layers of cubodial cells surrounding oocytes; produced E2 Antral: antrum: fluid filled cavity (E2) - Dependent of LH and FSH (also called tertiary or Graffian follicles); right before ovulation; fluid filled causes it to burst - Only one dominant follicle will release an egg during ovulation; others break down

Answer 249

Hemorrhagic: - Initial corpus structure - Bloody from rupture vessles (can feel burst) - right after the follicle bursts Luteum: - Structure comprised of luteal cells -Secretes prgesterone (P4) to maintain pregnancy - If no fertilization, goes away - Empty follicle turns into this to prepare for pregnancy Albicans: - In absesne of pregnancy, corpus leteum regresses into white small structure -Eventually disintegrates

Answer 250

Structure: 1. Theca externa 2. Theca interna 3. Granulosa cells 4. Cumulus-oocyte complex Function: - Makes estadiol (E2) regulates ovarian and uterine cycles - Houses and protect the maturing oocyte

Answer 251

Externa: - Loose connective tissue - Surrounds and supports follicle Interna (like internal test in bal): - Just beneath the theca externa - LH receptors!!!! LI - Produce andorgens (test) (theca outer) Granulosa cells: - Mural granulosa cells line inner part of basal lamina FSH receptors!!!!!! GF - Convert androgens into estradiol (E2)

Answer 252

- blood vessels make up about 50% of volume - luteal cells make up 30% - reminaing 20% (pericytes, firbocytes, nerves, immune and smooth muscle cells) - High proliferatoin and activty of cells - Luteal cells make progesterone

Answer 253

1. Trasnported using - Low density lipoporteins (LDL) - High density lipoproteins (HDL) 2. Luteal cells express LH receptors 3. Activates adenylyl cyclase 4. Converts ATP to cAMP 5. Activates protein kinases - enhance internalization - acitvates cholesterase - activates StAR protein 6. Cholesterol converted to pregnenolone 7. Pregnenolone converted to progesterone (P4) Progesterone is made from cholesterol (carried in LDL and HDL) - Luteal cells have LH receptors LH (luteinzing hormone) binds to them - LH activates signalling patheay in cell Luteal cells have LH receptors!!!; mediate cholesterol from pregnelone to prgesterone

Answer 254

HPG axis 1. Hypothalmus 2. Pituitary gland 3. Gonads 1. Hypothalamus secretes GnRH to pituitary gland 2. Pituitary gland releases FSH and LH (gpnadotropins) into the systemic circulation 3. LH and FSH reach ovaries (ovarian follicle and CL corpul luteum cells have LH and FSH receptors) 4. Ovaries make E2 (follicular phase) or P4 (luteal phase) 5. Feedback mechanisms mediate endocrine response

Answer 255

Stimulate the growth and proliferation of granulosa cells in ovarian follicles - Stimulates production of FSH receptors on granuloma cells - Results in increase senstivity to FSH - Less FSH needed to stimulate selected follicles - Stimulates aromatase production and increased enzymativ activity in granulma cells (converts test to estradiol)

Answer 256

Luteinzing hormone - Stimulates theca interna to produce test - Test diffuses into GC - Stimulates production of LH receptors on outer GCs - Results in oocyte meisosi resumption!!!!!! - High concetrations after LH surge - Weakens follicle walls and collapse folllicle=ovulation! - Undeces formation of corpus luteum

Answer 257

1. GnRH from hypothalamus to piuitary gland 2. LH and FSH get released from pituitary gland 3. Theca cells - LH binds to them - Makes test 4. Granulosa cells - FSH binds GCs recruitment of aromatase - Make test to estradiol

Answer 258

- Estradiol main estrogen secreted by follicles into the ovaries - E2 stimulates production of FSH recepotrs (inreased sensitivity to FSH) - E2 stimulates production of LH receptors - Establishes dominant follicle - Increased E2 in the antral follicle induces positive feedback in the pituitary gland - Regulates ovulation - Increased E2 during dominaint follicle stage induces an LH surge 2 days before ovulation - LH surge changed follicle structure, weaking follicle walls and increasing antral pressure - Follicle ruptures, releasing the cumulus oocyte complex

Answer 259

- LH surge converts remaining granulosa and theca cells into luteal cells= luteinization - Luteal cells make P4 and E2 sustains endometrium development - P4 stimualtes endometrial gland secretions while E2 stimulates spiral artery development

Answer 260

- P4 and E2 levels decrease causing menstration - Menstural discharge around 80 mL of blood, fluid and cell debris from upper layer of endometrium expoulses from uterus - Overt meses: endometrial spiral arteries responsible for menstral bleeding (primates); like overies humans - Covert menses: endometruim shed without bleeidng due to lack of endomterial spiral artieres (other mammals): estrus cycle

Answer 261

Ovarian cycle controls egg development and hormone production, and uterine cycle prepares the womb for pregnancy E2 builds up lining and P4 maintains it

Answer 262

1. Proliferative phase - Occurs during follicular phase - Increased E2 stimulates growth of endometrium - Before ovulation 2. Secretory phase: - Occurs in luteal phase - Increased P4 from corpus luteum stimualtes development of uterine glands - Endometrium grows in thickness due to E2 and P4 - Makes lining thicker due to E2 and P4 - Uterus prepares for possible pregnancy 3. Mensrual phase: - Necrosis and sloughing of endometrium - Result of decrease in ovarian hormone secretion (e2 and p) during late luteal phase

Answer 263

- Linked to luteal phase (after ovulation, before menstruation) - Needs ovulation and corpus luteum formation - Hormone changes affect serotonin, brain chemical linked to mood Goes away with: - Menopause

Answer 264

- Synthetic estrogen and progesterone 1. Override the system with high connetration of ovarian hormones 2. Negstive feedback inhibtion of pituitary secretions 3. No LH surge means ovulation never occurs - Stimulates a false luteal phase

Answer 265

- Estrogen important for cardiovascular health, bone health and behaviour - At menopuase, ovaries are depleted of follicles and stop secreting estrogen (they change at ovarian level not pituiary level) - Menopause associated with increased risk of osteoporosis, hot flashes, and aging - Weak form of estrogen (estriol) made in adipose tissue (females with more adipose tissue have higher elvels or estorgen and are at less risk of osteoporosis) (fat tissue)

Answer 266

Folliculogenesis: the continuous process of developing a follicle (small sac in the ovary) that holds an egg. it happens in cycles, leading to ovulation; happens every cycle and prepares egg for ovulation Oogenesis: the discontinous process of developing an egg (ovum) starts before birth, but pauses at different stages, completing only when fertilization occurs; oogenesis is a longer process that starts in fetal life, pauses, and only finishes if fertilization happens (develops a mature egg)

Answer 267

- Formation and genotypic maturation of female gametes - Oogenesis beginds during embryoinc development of the female and continues throughout her lifetime - Oocytes develop a complex cytoplasm during maturation - Completion results in an ovum that sustains embryonic development

Answer 268

COC= cumulus oocyte complex Cortical Granules (multiple grand gesture) - Enzymes preventing polyspermy (multiple sperm fertilizing the egg) Zona Pellucida - Protective membrane - Faciliates sperm binding Corona radiata - Cumulus granulosa cells surrouding the oocyte - Intensive crosstalk with oocyte- coordinate oocyte development - Mediated by gap functions

Answer 269

Cytoplasm provides nourishment to the embryo-> vitellus or yolk - Conserve nutrients and minimize waste, only genetic material is extruded with polar bodies - Asymmetric cell division - Ensures cytoplasm is conserved - Sustains early embryonic development until implantation in the uterus

Answer 270

In oocytes due to off-center spindle positining - Results in one large cell (oocyte) and one small polar body - Oocyte keeps most of the cytoplasm to support future embryo development Timeline: - GV to GVBD to MI to PB1 to CSF arrest MII (stages of meiosis)

Answer 271

Small since they dont need to store extra nutrients for development (get from mother)

Answer 272

1. Oocytogenesis - Mitotic divsions resulting in more oogonia - Occurs during embryonic development 2. Ootidogenesis: - First meitotic divison - Results in secondary oocyte and polar body - Occurs after puberty, cyclically 3. Oogenesis: - Completes second meiotic division - Results in mature ovum and two polar bodies - Occurs after fertilization in mammals

Answer 273

- Meiosis I stops at Prophase I - Happens before birth (during fetal development) - Primary oocyte stays frozen in Prophase I until puberty - Meiosis I resumes and completes at ovulation - Just before ovulation primary oocyte finshes meisosi I, forming secondary oocyte and a polar body - secondary oocyte is frozen in metaphase II until fertilization occurs - meiosis II only completes if fertilization happens

Answer 274

Fertilzed egg

Answer 275

- Mitosis of oogonia and differentiation into primary oocytes 1. Oogonia in the differentiating ovary divide by mitosis - mitotic divisions determine the size of ovarian reserve 2. Mitosis continues until formation of primoridal follicles 3. Oogonia differentiate into primary oocytes - Divide through mitosis before birth - Determines the number of eggs a female will have for life - Mitosis continues until primoridal follicles (egg containing structures form) - Oogonia then develops into primary oocyte which pause in prophase I until puberty

Answer 276

- Primary oocytes undergo meiosis I to make a secondary oocyte and polar body Embryonic phase - Onset of meiosis I and nuclear arrest of primary oocytes Adult phase: - Resumption of meiosis I, resulting in secondary oocyte

Answer 277

During embryonic development.. 1. Primary oocytes develop a germinal vesicle (GV) 2. Primary oocytes enter meiosis I 3. Meiosis I arrested at the diplotene stage of Prophase I - All primary oocytes are arrested in Prophase I at birth - purpose of nuclear arrest to protect DNA from damage

Answer 278

Onset of puberty: 1. Formation of zona pellucida (ZP) - Covers and protects the entire oocyte - ZP proteins important for fertilization 2. Formation of gap junctions - Cytoplasms communication that corsses the zona pellucida - Crtiical for commuinication between the oocyte and granuloa cells (GC) 3. Oocytes undergo growth of cytoplasm volume and cytoplasmic maturation 4. Oocytes arrested at prophase I resume and complete meiosis I

Answer 279

After LH surge - High LH concentration stimulates LH recepotors on mural GCs What happens with a deterioration of gap junctions? - reduction of oocyte cAMP - deactivation of kinases - activation of MPF

Answer 280

1. Gap junction breakdown? Granulosa cells send cGMP into oocyte through gap junctions - cGMP inhibits PDE3A which keeps cAMP levels high and prevents meiosis from resuming - LH signalling cuases gap junctions to deteriorate,reducing the transfer of cGMP into the oocyte 2. Loss of cGMP leads to cAMP breakdown - Less cGMP, PDE3A is activated, which breaks down cAMP - Since high cAMP levels were keeping the oocyte in Prophase I, their drop triggers meiosis to resume 3. Activation of MPF (maturation promoting factor) - drop in cAMP allows MPF (maturation promoting factor) to activate, which pushes the oocyte past prophase I into metaphase II (preparing for ovultation)

Answer 281

Loss of gap junctions; gap junctions allow the cGMP to come in

Answer 282

1. Crossing Over (during meosis I) Segments of one CHS crossingover to a homologous CHS - Results in a random assortment of DNA segments between chromatids - Ensures genetic diversity in daughter cells 2. Completion of meisois I - Asymetric cytoplasmic divsion - extrusion of 1st polar body

Answer 283

- Characterized by continuation of meosis II and nucelar arrest of secondary oocytes - Ovulation arrested at the metaphase II stage

Answer 284

Oocyte: not fertilized Ovum: fertilized

Answer 285

- Spermatozoon - Oocyte structure

Answer 286

Male: testes Female: ovaries

Answer 287

- Non-motile, infertile sperm passively transported to epididymis for spermiation Duration: 4-12 days - Upon ejaculation, sperm in seminal fluid pass through ducts deferens and mix wth secretions 1. Secretions from seminal vesicles (fructose and prostaglandins) 2. Prostate gland (citric acid, acid phosphate, zinc and magnesium ions) - Sperm starts in testes but isnt motile yet - Moves into the epidymid where matures (4-12 days) - During ejaculation sperm travels through ductus deferenc and mixes with fluids from

Answer 288

Uterus: horses, dogs, pigs, rodents Cervix: pigs and horses Vagina: cows, sheep, cats, rabbits, humans

Answer 289

1. Sperm deposited in upper vagina (rapid elevation of pH to increase survival) 2. Passage through cervix (fast and slow phases) 3. Passage through uterus/uterine horns 4. Entry into oviducts, where fertilization occurs 5. Passage up ovidcuts by flagllar movement and contractions of oviducts

Answer 290

pH goes from 4.3 to 7.2 in 10 seconds (only lasts for few mins enough for pserm to approach cervix at a pH of 6-6.5 optical for sperm motility)

Answer 291

1. Major barrier to spermatozoa - Cervical cells secrete mucous - Viscous and gelatinous- inhabitable for sperm - Cervical rings and folds inhibit sperm travel 2. Sperm reservoir - Cervical folds and crypts - Sperm get trapped in crypts - Process facilaited by cervical mucus - More sperm in cervical reservoir= more sperm reaching oviduct

Answer 292

Viscous prevents sperm movement

Answer 293

watery- faciliates sperm motility

Answer 294

Rapid: - Sperm penetrate sialmucin - Quickly go through cervical canal - Adided by muscular contraxtions - Reach uterus Slow: - Sperm swim through cerivcal mucus (2-3 mm/hr) - Sequential release - Slow release ensures conties availabilty of sperm to enter oviduct for fertilization - Can laat up to 3 or 4 days after ejaculation - Increases chances of sperm

Answer 295

1. Sperm moves towards oviducts - Egg releases chemcisl signals (chemoattractants) that help guide sperm - Uterine muscle contrations help push sperm toward the oviducts 2. sperm reaches the utero-tubal junction - Gatway between the uterus and oviducts, where sperm continue their jounrey toward the egg 3. capacitation (final sperm maturation) - sperm undergo changes in female reproductive tract - changes prepare sperm for fertilization and help them pentrate the eggs protective layer (zona pellucida)

Answer 296

- Aleration of glyocprotein surface of sperm under infleunce of female tissue secretions within the reproductive tract which enables zona pellucida penetration (which allow for binding to zona pellucida or oocyte)

Answer 297

- Narrowest part of oviduct stores sperm until ovulation, helping regulate fertilization timing 1. Sperm enters oviduct - sperm reach isthmus and attach to oviduct epithelial cells (OECs) 2. Calcium levels drop in sperm - prevents premature activation and keeps sperm in a low-energy state 3. Protein production by oviduct cells - OECs release proteins that stop sperm from undergoing capacitation too early 4. Progesterone at ovulation releases sperm - when ovulation happens, progesterone rises, triggering sperm release from isthmus so they can reach egg

Answer 298

1. Caclium channels activate catsper proteins - Before activation: caclium levels in sperm are low, so motility is weak - After activation: progesterone from oviduct and other signals open catsper calcium channels, allowing Ca2+ to enter sperm more calcium stronger it is

Answer 299

1. Immediate transport (vagina to cervix) - some sperm lost due to - retrograde loss (sperm goes out) - phagocytosis (immune cells attack sperm) - rest enter cervix and uterus 2. Cervix- sperm selection - Privelged pathways allow only the strongest, most motile sperm to pass - Non-motile sperm and abnormal sperm removed - Cervial mucus helps filter out defective sperm 3. Uterus- sperm activation - capicitation (early stage) being preparing for fertilization - More sperm removed by immune cells (phagocytosis) 4. Oviduct (final sperm actication and hyper activation) - capitation is complete sperm gaims ability to fertilize egg - hyperactive mottility beings isthmus 5. Fertilization in the oviduct (ampulla region) - Acrosome reaction occurs, sperm release enzymes to break through eggs layer

Answer 300

1. Ovulayion occurs - dominant follicle bursts, releasing the cumulus-oocyte complex (COC) egg surrounded by protective cells 2. Fimbria help capture egg - Fimbria (finger like projections) of the infindibulum sweep the egg into oviduct 3. Cilia guide the egg to the ampulla - once inside the oviduct, cilia move the egg toward the ampulla where fertilization occurs

Answer 301

1. Sperm arrives 2. Acrosome reaction (enzymes pentetrate eggs layer) 3. Penetratin of zona pellucida 4. Membrane fusion 5. Fusion of nuclei

Answer 302

Remove the cumulus cells surrounding it Removes by: 1. Hyaluronidase - Found on surface of capacitated sperm - Breaks down cumulus cell using hydrolytic (digestive) action 2. Sperm motility - Use strong movements (hyperactivation) to break apart the cumulus cells

Answer 303

Bind to zona pellucida proteins - ZP proteins only allow species-species binding - ZP proteins prevent any other sperm to enter ovum after fertilization - Binding to ZP triggers acrosome reaction (which allows pserm to enter the egg)

Answer 304

1. Membrane fusion - sperm plasma membrane fuses with outer acrosomal membrane 2. Enzyme release - Pores open, relasing acromsomal enzymes such as Acrosin and hyaluronidase that digest the zona pellucida 3. Exposure of fusion proteins - inner acrosomal membrane exposed, allowing sperm to bind directly to egg membrane

Answer 305

- After sperm pentetrate zona pellucida and reach perivitelline space (area between the zona and egg membrane), cortical granules migrate to periphery of oocyte - Oocyte plasms membrane fuses with equatorial segment - Immediate mebrane depolarization and the fertilzing sperm is engulfed - Cortical granules are released into preivitelline space - Sperm nuclear membrane disappers and the nucleus decondenses

Answer 306

- Fast block of polyspermy - Rapid depolarization of the vitelline membrane - Triggered by influx of Na+ ions from NaK+ pumps - Results in electrical barrier to sperm entry - Temporary and only lasts few mins

Answer 307

- Permanent structural change that happens after fertilization - Slow block of polyspermy Relaxed enzymes: - Peroxidases - Harden glycoprotein to form impentetrable layer Glycososaminoglycans - Attract water into the perivitelling space - Fertilization envelope Proteases - Destroy sperm binding sites - Prevents other sperm from binding to ZP proteins

Answer 308

1. Sperm capacitation and chemotaxis - Sperm become fully mature and swim toward egg 2. Acrosome reaction - Sperm release digestive enzymes to break through zona pellucida (outer egg layer) 3. Sperm-egg fusion - Sperm bind to egg membrane and release PLC zeta into thr egg - Cortical granukes released to prevent multiple sperm from entering (block to polyspermy) 4. Activation of PLC zeta enzyme - triggers the breakdown of PIP2 into DAG and IP3 (important singalling) 5. Calcium release from ER - IP3 binds to receptors on ER, causing Ca2+ release in egg 6. Egg activation and cell division resumption - Calcium singal activates the egg, allowing it to resume the cell cycle and being embryonic development

Answer 309

After fertilization, calcium waves trigger changes in the egg that allow it to resume development and start dividing What happens? 1. Calcium signals activate NAD+ kinase, helps build new cell wall membranes 2. Cyclin (protein that atops cell division) broken down allow meiosis to continue 3. The egg starts making new proteins, copying DNA, and preparing for development - Allows extrusion of second polar body and formation of maternal pronucleas

Answer 310

1. Completion of meiosis results in a female pronucleus 2. Sperm nucelus decondenses to form male pronucleus 3. Sperm centriole forms microtubles that integratr with ovum microtubles, drawing the pronucelei closer 4. Fusion of two pronuclei: - cellular membranes break - chromatin from both intermix beofre condenging into CHS - embryonic development begins

Answer 311

- Inability to concieve after one year of unprotected intercourse - Caused by a myriad of endogenous and exogenous factors - Hormones, reproductivr tract developmeny, homeostasis - Epigenetics and genetics - Damage related to disease conditonis ex cancer and its treatment Male infertility: - conditoins affecting spermatogeneiss - Affecting sperm quantity - Sperm quality - Environmental factors - Probelsm with sperm reaching the female reproductive tract Female: - Ovulation disorders - Condtions of uterus - Fallopian tube damage or blockage (prevents fertilization) - Endomteriosis - Priary ovarian insuffiency - Pelvic adhesions (scar tissues blocking egg movement) Affects 1 in 7 couples worldwide

Answer 312

AI (artifical insemination) - Also called intra-uterine inseminatino - Sperm is washed and injected into uterus In-vitro fertilization (IVF) - Ooccytes are harvested and fertilized in lab - Embryo transfered into carrier or surrogate

Answer 313

Classic IVF - In-vitro maturation:oocyte maturatoin (FSH, LH, E2) - In-vitro fertilization: incubatr with sperm (18hr) - In-vitro cell culture: incubate with unhatached blastocyst Intracytoplasmic sperm injection (ICSI) - Treatment for severe male factor sterility - perm quality (motility and morpholoy) assessed - Sperm injected into secondary oocyte cytoplasm

Answer 314

- Ciliated epithelium of oviduct moves embryo toward uterus - Mammalian cleavage occurd every 12-24 hrs (dividong and gorwing) - End goal: implanatation of the embryo via burrowing into the uterine endometrium - Day 8-9 goes into the uterine lining (blastocyst hatches from zona pellucida the ball of cells)

Answer 315

In mammals it is a rotational asnchronous cleavage - Initial divisions of zygote to form early embryo - Involves rapid mitotis divsions with no growth pahses - Reulsts in idential daughter cells called blastomeres - Blastomeres become smaller with each division - Blastomeres up to 8-cell stage are totipotent (can still become any cell in body)

Answer 316

- Blastomeres tightly adhere, forming the 16-cell moruka - Embryo is more compact and cells lose individual identity - Mediated by calcium-activated cell adhesion molecules - E-cadherin- a cell adhesion protein present during early embryonic development - Epithet- associates with E-cadherin

Answer 317

Inner cell mass - Embryoblast - Gap junctions form - Becomes the embryo proper Outer cell mass - Trophoblasy - Tight junctions form - Becomes fetal placental contribution - FOrms other extraembryonic membranes

Answer 318

- Occurs prior to implantation - EMbryo breaks through zona pellucida due to proteases secreted by blastocyst - Inability to hatch is one cause on infertility - Altered zona pellucida - Absence of proteases - Embryos lacking zona pellucida protein leading to premature hatching

Answer 319

Apposition and adherence: - Embryonic pole adjacent to uterine endometrium - Adhesion via cell adhesion molecules - LIF involvement, L-selectin, trophinin Penetration: - Syncytiophoblast, differentiated multinucleated trophoblast cells - Invasive: secrete digestive eznymes, works its way into uterine tissue - Establishes contact with matenral blood vessels Decidual reaction: - Uterine tissue responds to invasion by setting up immunological barrier (the decidua) - Becomes the maternal portion of placenta

Answer 320

- A process where the bilaminar disc (two-layered embryo) develops into 3 germ layers - Happens by week 3 of development

Answer 321

Epiblast= maternal portion (becomes embryo) Hypoblast=embryonic protion (helps form extra embryonic structures)

Answer 322

Ectoderm Mesoderm Endoderm

Answer 323

- Highly complex and convserved developmental process forming internal organs and systems 1. Ectoderm - Intergumentary system (epidermis) - Nervous sytem 2. Mesoderm - Circulatroy - Intergumentary system (dermis) - Muscokeletal - Urogential 3. Endoderm - Digestive - Glandular tissues - Respiratory

Answer 324

Chorion - fetal portion of placenta - gives fetal oxygen and nourishment Amnion - Encloses embryo - Filled with amniotic fluid - Provides physical protection from impacy Yolk sac - Intitial size of blood cell production (hematopoiesis) - Synthesizes a variety of proteins - Primoridal germ cells (PGCs) Allantois - Independent waste storage and repsoriation (non-mammals)

Answer 325

Identical (monozygotic twins) - One fertilized egg splits into 2 embryos - depending on when it splits may share of have seperate - Placenta (chorion) and amniotic sac - If split is late (13-15) conjoined twinis fraternal (dizygotic twins)- two seperate eggs fertilized by 2 sperm - each has its own placenta and amniotic sac

Answer 326

Happens when a fertilized egg implants on outside of uterus, dangerous and cannot develop Common locations 1. Fallopoain tube most common (ampullar)(80%) 2. Isthmic (5-10%) - implants in narrow part of fallopian 3. Ovary (0.15%-3%) - rare, egg implatns in oveary instead of uterus 4. Cervix - very rare 5. Abdomen (1.3%) 6. Intramural, myometrial, or peritoneal (less then 1) - plants in uterine muscle or other unsuaul 7. Intestinal (2.5%) - implsnts at junctino of fallopian tube and uterus

Answer 327

Germinal period: - Fertilization until implantation - Zygote until embryonic disk Embryonic period - Gastrulation until 8th week of pregnancy - Neurulation - Organogenesis Fetal period - From 9th week of pregnancy until parturition - Age of viability 22 to 28 weeks

Answer 328

- Corpus luteum synthesizes - Progesterone keep endometrium intact - Progesterone, estrogen, inhibin: feedback supression to pituitary

Answer 329

- Synctiotrophoblast cells synthesize human chrionic gonadtropin (hCG) - Maintains the corteus letuem until week 5-6

Answer 330

Produces important hormones to support pregnancy hCG: maintans pregnancy in early stages Estriol (E3): helps uterus grow and prepares breasts for milk production Progesterone (P): prevents contractions, keeps cervix closed, and supports milk glands PTHrP: takes calcium from mothers bone for baby CRH: helpsbaby lungs develop

Answer 331

- Detects hCG (hormone present in urine during early pregnancy) How it works: 1. Urine sample is applied to test 2. If hCG present: two lines appear (pregnant) 3. If none only 1 line

Answer 332

- Powerful contractoins of the myometrium in the uterus are needed to expel fetus in a sequence of events called labor Uterine contractions mediated by: 1. Oxytocin - Polypeptide hormone - produced in hypothalamas, released by posteiror pituitatary - produced in uterus 2. Prostaglandins - Cyclic fatty acids with paracrine functions - Produced by uterine glands - PGF2 alpha and PGE2

Answer 333

1. Fetal hypothalamus releases CRH (corticotropin releasing hormone starts labor) 2. Fetal anterior pituiatry relases ACTH (aderenocorticotropic hormone), which singalds the adrenal glands 3. Fetal adrenal glands release DHEAS and cortisol which prepare body for birth 4. Hormones activate 3 key pathways: - Positve feedback (more contractions) -Uterine sensitivity (makes iuterus respond more to labor hormones) - Oxytocin pstheaay (triggers strong contractions for delivery)