Unit 6 Lecture Flashcards
Define mitosis
For growth and repair, turning a diploid cell into two identical diploid cells
How many pairs of chromosomes do we have
23
Define meiosis
Production of gametes, one diploid cell produces 4 diploid s at a time
Where does meiosis occur?
Happen in the ovaries or testes
Define dimorphic
Meaning two sexes
What do male and female gonads produce?
Male gonads = testes = sperm
Female gonads = ovaries = eggs
What causes the production of gametes?
Hormones
Where does sex cell production occur?
In útero
How many chromosomes do diploid cell have?
46 chromosomes
How many chromosomes did haploid cells have?
23 chromosomes
What are oogonia
Germ cells for females
What are spermatogonia
Germ cells for males
Get unit two notes for mitosis
What is happening during prophase 1?
The chromosomes from mom and dad get close and perform a cross over to increase genetic diversity
What is primary gamete
Duplicated Diploid cells with 46 chromosomes
What is secondary gamete
Haploid cells with 23 chromosomes and need of one more round of duplication
What is final stage gamete?
A Haploid cell with 23 chromosomes that have a single copy of each chromosome(chromatids
How many sperm are produced from a spermatocyte
1 spermatocyte = 4 sperm
What is the timing for males gametogenesis
Before birth immature lots of speratogonia are produced through mitosis . At birth production of sperm is quiescent
At puberty spermatogenesis begins again
What is the timing for gametogeneis for females?
Before birth they complete mitotic divisions to create all primary procures (~ 500,000 at birth)
Primary procures go quiescent after duplicating chromosomes
At puberty 1 primary procure is chosen for maturation and go through meiosis 1.
Produces a secondary oocyte and first polar body
At 2 nd neurotic division begins where the secondary oocyte stops at the fallopian tube and wait for sperm.
Ovulation occurs
If fertilization occurs one set of chromatids combine with a sperm genome and other is casta away as the 2nd polar bodyv
Define monozygotic twins
Aka identical twins have identical DNA , fertilized by one egg.
Where the zygote splits into two
Define dizygotic twins
Like leia and Luke Aka fraternal twins have different DNA , two separate eggs produced during one ovarian cycle and ultimately fertilized by genetically different sperm
Define nondisjunction
When a gamete end with more or less than 23 chromosomes
What is klinefelters syndrome
Chromosomes in male are XXY causing problems with small testicles, ⬇️ fertility
Define Turner’s syndrome
Chromosome is only X, infertile & short in stature
What hormones are released by hypothalamus
Gonadotropin releasing hormone
What hormones are released by anterior pituitary gland
Lutenizing hormone (LH)
Follicle stimulating hormone (FSH)
What does litenizing hormone do?
What do follicle stimulating hormone do?
Examples of steroid hormones
Testerone, estrogens or progesterone that regulate gamete production
Why is cholesterol good?
It helps with production of progesterone, estrogen, testerone
What can testerone be converted into?
Dihydrotesterone
Aroma taste inhibitors
Are meant to inhibit cholesterol which do something for hormone production and fight breast cancer
What are the 3 estrogens?
Estradiol, estriol, esterone
What does estriol do?
Main estrogen that are post puberty but not pregnant
What does estradiol do?
Main estrogen during pregnancy
What function is esterone
Main estrogen after menopause
Tell me the male spermatogensis control
Hypothalamus sends a pulse(every 90 minutes) for GnRH to the anterior pituitary gland .
The anterior pituitary gland release FSH to stimulate Sertoli cells.
Stimulate Sertoli cells stimulate spermatogenesis
Sertoli cells produce androgen binding protein. Which help carry testerone in the blood.
The anterior pituitary gland release LH to stimulate interstitial cells. Interstitial cells produce testerone that bind to androgen binding cells
What are Sertoli cells?
Cells that make up the walls of the semiferous tubules
How many sperm do males make a day?
100-300 million sperm per day after puberty
What is in the head of a spermatozoa made of? Called?
Composed of acrosome and nucleus
What is the head of a mid piece of a sperm
Centrioles and mitochondria
Define gametogenesis
The production of sex cells in both males and females
Define spermatogenesis
Production of sperm cells
Define oogenesis
Production of egg cells
A cell that has two copies of every chromosomes is called?
A diploid
A cell that has only one copy of every chromosome is called?
A haploid
What is a type of cell division that used for growth and repair in tissues?
Mitosis
What is the description of a diploid cell duplicates all its chromosomes and organelles before dividing into two identical daughter cells?
Mitosis
What is a type of cell division that only happens in the ovaries or testes?
Meiosis
What type of cell division starts as a diploid cell and produces 1-4 haploid cells after two rounds of division
Meiosis
How many pairs of chromosomes do diploid cells have?
23
What is the first step of meiosis that includes the germ cell to go through interphase to duplicate all organelles and chromosomes.
Primary gamete
Define crossing over
Process to exchange genes between homologous chromosomes. Occurs during prophase 1
During anaphase 1 homologous chromosomes do what so that each pair get pulled to an opposite side of the dividing cell
Separate .
At the end of meiosis 1 there are two haploid cells that both have a duplicate copy attached. What are these gametes called?
Secondary gametes
During anaphase 2 each sister chromatid will do what? That causes the centromere holding the two identical chromatids together to break
Split
What is the final stage gamete?
Process of meiosis start with one spermatogonium and ÷ into 4 gametes which will mature into sperm
What are polar bodies?
For females the procress of meiosis start with one oogonium and ÷ into only one mature egg. Other three cells containing genetic material will become a polar body and ultimately disintegrate
What is gonadotropin releasing hormone?
It’s released from the hypothalamus in males every 1.5 hours. This hormone triggers the release of two anterior pituitary hormones
What is follicle stimulating hormone?
Hormones from anterior pituitary gland that stimulates servility cells in the testes to produce androgen binding protein, inhibit and paracrine signals needed for spermatogenesis
Where is the gonatroponin releasing hormone released?
Hypothalamus
What is luteinizing hormone
Anterior pituitary hormone that stimulates interstitial cells of leading to produce testerone.
Why is testerone important?
Critical hormone that supports male secondary sex characteristics and aids in sperm production
Tell me about the follicular phase
Part of the menstrual cycle that actually composed of two espérate cycles of events that happen in the ovaries and uterus. The first half of the ovarian sucker 1-14 days is the follicular cycle
During anaphase what hormone is produced by the anterior pituitary gland that stimulates the development of new follicle in the ovaries
Follicle stimulating hormone
As a follicle develops between 5-13 what hormone is secreted higher and higher
Estrogen
Just before ovulation in females there’s in ⬆️ of what hormone that’s released from the anterior pituitary gland
Luteinizing hormone
After ovulation , in the second half of the ovarian cycle during days 15-28 is called the what phase
Literal phase
During the luteal phase what hormone is the dominant ovarian hormone?
Progesterone
What hormone is produced by the corpus luteum which is what remains of the follicle in the ovary
Progesterone
The uterine cycle has three sub phases. This is the cycle is the first of those subphases and is triggered by low levels of estrogen and progesterone. This does not indicate implantation occurred in the previous menstrual cycle.
Menses
What uterine cycle removes old uterine lining during a period of bleeding?
Menses
What is the second uterine phase
Proliferative phase
What section of the uterine sub phase is stimulated by raising estrogen levels from the ovaries. It causes the thickening of the uterine lining
Proliferative phase
What is the third phase of the of the uterine subphase
Secretory phase
What subphase of the uterine cycle is stimulated by high levels of progesterone from the ovaries? It causes an extra thickening of the uterine lining from the Proliferative phase .
Secretory phase
What subphase adds additional thickening of the uterine lining in anticipation of pregnancy along with ⬆️ vascularuzation and deopositing of fuel molecules like glycogen and lipids for a potential embryo
Secretory phase
What is the structure that is an accessory digestive organ? It releases liquid containing digestive enzymes (carbs and lipids) into the mouth during chewing
Salivary glands
What is the muscular tube that transport food from the mouth to the stomach
Esophagus
What organ is where swallowed food and drinks is further combined with digestive enzymes and hydrochloride acid?
Stomach
What organ is the compartment where protein digestion happens
Stomach
What is the accessory digestive organ that located inferior and posterior to the stomach?
Pancreas
What is the accessory digestive organ that has endocrine and exocrine function? These help with digestion in the small intestine
Pancreas
What organ is highly coiled section of the digestive tract where vast majority of biomolecule digestion and absorption occurs
Small instestine
What is the final compartment of the digestive tract that absorbs the last remnants of water from the digested food and condenses it into feces?
Large intestine
What organ is the destination that triggers defecation reflex
Rectum
What organ filters and detoxifies the blood ?
Liver
What organ is and important storage site of glycogen, iron and many vitamins?
Liver
What organs structures as qualifies as accessory digestive organ since it synthesizes bile?
Liver
What is bile?
A substance created in the liver that aids in emulsification and digestion of lipids
What organ stores bile and is influcned by hormones? Which influenced releases bile into the small intestine
Gall bladder
Define digestion
Chemical and mechanical breakdown of foods into smaller units . These unit are small enough to go to intenstial epithelium in the body
Define absorption
Active or passive transfer of substances from the lumen of the GI tract to the extracellular fluid
Define motility
Movement of material in the GI tract as a result of muscle contraction
Define secretion in regards of the digestive study
Transepithelial transfer of water and ions from extracellular fluid to the digestive tract lumen as wall as release of substance synthesized by GI epithelial cells
What nervous system helps coordinate digestive function
Enteric nervous system
Define peristalsis
Progressive contracted wave like movement by muscle from one section of the GI tract to the next
Since fat is not absorbed directly into circulation like monosaccharides and amino acids. These lymph vessels are the route by which fats enter the circulation
Lacteals
What are endopeptidases
They attack long peptide bonds into smaller fragments
Define exopeltidases
They release single amino acids from peptides es by chopping off the ends one at a time
What levels do carbs digestive in order to be absorbed in the blood
Monosaccharides
What level should proteins digested down into what level in order to be absorbed into the blood
Monomer, amino acids
Ingested triglycerides will digested down to what level in order to be absorbed?
Fatty acids, momoner
Monosaccharide examples
Glucose, fructose, galactose
What hormone targets the gastric and intestinal smooth muscle?
Motilin
What hormone is stimulated by fasting and stimulates the migrating motor complex?
Motilin
What hormone targets the endocrine pancreas and is stimulated by mixed meals that include carbs, fats that enter the small intestine
Glucagon like peptide 1
What hormone stimulates insulin release and inhibits glucagon release?
Glucagon like peptide 1
What hormone targets the ECL cells and parietal cells of the stomach? It’s stimulated by peptides and amino acids in the stomach or neural reflexes
Gastrin
What hormone stimulates gastric acid secretion and mucosal growth
Gastrin
What hormones is stimulated by fatty acids when they enter the small intestine? It targets the gall bladder, pancreas and stomach?
Cholecytokinin
What hormones stimulate gall bladder contraction and pancreatic enzyme secretion?
Cholecystokinin
What hormone inhibits gastric emptying and acid secretion
Cholecystokinin
What signal molecule is stimulated by acid entering the small intestine and targets the pancreas and stomach?
Secretin
What signal molecule stimulates bicarbonate release and inhibits gastric emptying and acid secretion
Secretin
What hormone targets beta cells of the pancreas that cause insulin g release?
Gastric inhibitory peptide
What hormone inhibits gastric emptying and acid secretion
Gastric inhibitory peptide & cholecytokinin
Define ingestion
Putting food in the mouth
Define mastication
Chewing and food mixed with salivia
Define deglutition
Swallow
Peristalsis
Squeezing by muscular contraction along and through the GI tract
Define segmental contractions
Responsible for mixing, aletnarting segment contract to causing mixing
What type of bond holds a polymer for fatty acid
Ester bonds
What type of bond is used for carbs
Glycosidic bond. Think carbs to glycogen to glycosidic bond
What type of bond is used for proteins
Peptide bond . Think P for protein and peptide bond
Examples of experiments secretions in the GI tract
Enzyme
Hydrochloride acid
Bicarbonate
Mucus
HEBM
What type of motility occurs at the mouth?
Mastication , regulation , ingestion
What secretions occur in the mouth?
Salivia , salivary amylase and salivary lipase
What is being digested in the mouth?
Fats (minimally) & carb
What absorption occur at the mouth?
Sublingual of different drugs
Are enzymes secreted in the esophagus?
Nope
What type of motility occurs in the stomach?
Segmental contractions
What secretions create chyme?
Hydrochloride acid
Zymogen
Gastric lipase
Mucus
HZGM
What secretions occurs in the stomach?
Gastric juices . Juices used to make chyme
What is digested in the stomach
Proteins and < 10% of fat
What is being absorbed in the stomach?
Aspirin and alcohol
What kinds of bonds is ester, peptide and glucocorticoids bonds?
Covalent bonds
What are chief cells? What do they secrete? The function? What their stimulus?
Secrete : pepsin , gastric lipase
Function : digest protein(pepsin), digest fats(gastric lipase)
Stimulus : ACH & acid secretion
What are D cells? What do they secrete? The function? What their stimulus?
Secrete : somatostatin
Function : inhibit gastric acid secretion
Stimulus : acid in the stomach
What are G cells? What do they secrete? The function? What their stimulus?
Secrete : gastric
Function : ⬆️ gastric acid secretion
Stimulus : ACH , peptides & amino acids
Define zymogens
Inactive form of secreted enzymes
Story of stomach secretion regulation
Which cells secrete HCL
What motility occurs in the small intestine?
Peristalsis & segmentation
What type secretions occur in the small intestine
Bile, pancreatic juice
What is digested in small intestine?
Protein, carbs and fats
What is absorbed in the small intestine
Monosaccharides
Amino acids
Fatty acids
Water
Electrolytes
What enzymes comes from pancreas to small intestine?
Bicarbonate , mucus and isotonic saline , bile and pancreatic enzymes
What activates trypsinogen to become trypsin
Enteripeptidase
What enzymes does trypsin activate?
Chymotroypsin, carboxypeptidase
Phospholipase
CCP
Bicarbonate mechanism
It’s like the parietal cell but flipped 180°
What enzyme is needed to make bicarbonate
Carbonic anhydrase
Story of carb digestion
Pancreatic amylase digested starch and glycogen to become disaccharides
What glucose polymers make up maltose, sucrose and lactose?
Maltose: 2 glucose
Sucrose : 1 glucose + 1 fructose
Lactose : 1 glucose + 1 galactose
How do we get monosaccharides absorbed in the blood
What is endopeptidase?
It clips amino acids chains in half to form 2 small fragments
It has pepsin in the stomach and trypsin and chymotrypsin in the small intestine
What does enzyme tell you when it ends with sin?
What does an enzyme tell you when it ends with ase?
What is exopetidases.
They will break the amino acid chain at the distal ends . Carboxylpeptidase and aminopeptidase are under the exopetidase umbrella
What does aminopeptidase do?
They break up amine group
What does carboxypeptidase do
It breaks up carboxyl groups in a amino acid chain
How do single amino acids move out of the lumen?
By the use of co-transport with Na+ (symport)
How are do peptides & tripeptides pass through the lumen
On the apical membrane. They need the help of memenrane transporters , SAT with H+
How do oligo- peptides move across of the lumen wall?
The use from the apical to the basolateral by transcytosis
What can amino acids and fatty acids in the digestion system?
They can release H+ ions into the solution
What do amino acids , di & tri pepetides enter to go to the liver?
Hepatic portal vein
How is fat digested & absorbed
It begins in the mouth & stomach. But primarily in the small intestine. While fat is in the small intestine bile arrives from the liver and emulsify the fat into micelles then cholesterol and free fatty acids.
Free fatty acids and monoglycerides simply diffuses through the apical membrane into the cell of small intestine .
Freer fatty acid go through smooth ER turn into triglyceride
Cholesterol goes through a carrier protein (NPCk1L1 transporter)
Cholera too combines with triglyceride and protein fragments equal chlyomicron
Chlyomicron use exocytosis to exit the basolateral membrane
Chlyomicron out of the small intestine cell to the lymph to vena cava
How do bile fat in fat digestion
A amphipathtic molecule emulsify fat into small droplets . It increases surface area so that other enzymes can break down the fat
What is a triglyceride composed of?
Monoglyceride + 2 free fatty acids
Where does primary fat digestion and absorption occur? Where else does it occur?
Primarily small intestine. Other location at stomach and mouth
What is Zeita?
A drug the decreases cholesterol carrier protein to treat patient with high cholesterol at high risk for heart disease.
What category of drugs blocks cholesterol carrier protein blockage to the liver
Statins
What type of motility occurs at the large intestine?
Peristalsis and segmentation
What secretions occur in the large intestine?
Mucus from goblet cells
What is digested in the large intestine?
None except by symbiotic microorganisms. Only proteins and polysaccharides and synthesize important vitamins
What is being absorbed in the large intestine?
Water, electrolytes and vitamins (B & K
What storage and elimination occur at the large intestine?
Temporary storage and defecation occur
How much energy is expended during basal metabolic rate?
60%
How many calories should males consume per day?
From ages 16-500 is 2400-2800
How many calories to consume for females
From ages 16-50. 2000-2200
What three S should we avoid?
Salt , sugar and saturated fat
How much energy is expended during thermic effect of digestion?
8%
How much energy is expended during lifestyle or activity choices
32%
What is positive caloric balance?
More caloric intake than caloric output
What is negative caloric balance
More caloric output than caloric intake
BMI table
Below 18.5 = underweight
18.5-24.9= normal
25.0-29.9= overweight
30.0 and above = obese
How to calculate BMI
Body mass index kg / height (²)
Down fall of BMI?
It is not measuring body fat. So it’s inaccurate towards muscular individuals
What is hydrostatic weighing
Submerging a person in water getting rid of their air and weigh them.
What is air displacement plethysmography?
volume and pressure inside the chamber are known.
When a person is in the chamber, decreased volume of air will increase pressure
What is bielectrical impedance?
See how much body fat someone has. Seeing the speed and electric goes through
How much of the American population is considered obese?
42%
Which populations are most recorded to be obese?
African American, Hispanic and Caucasian adults
What waistline measurement indicated excessive fat?
> 40” for men
35 “ for women
What is the measurement for hypertension
130/85 mmhg
What is the measurement for high fasting blood glucose?
100-125 mg/dl
How much should mean consume for sugar?
No more than 36 grams
How much added sugar should women drink?
25 grams per day
Define gamete
A mature haploid cell of male or female. They have the ability to unite with the opposite sex for reproduction
Define acromegaly
Too much growth hormone is given and causes ⬆️ in jaw formation and other bone psrt
