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Pathway of Sperm

Created in seminiferous tubules --> travel to lumen (opening) in center of seminiferous tubules --> move through lumen to epididymis --> Mature and stored in epididymis --> Vas Deferens --> Urethra (All Accessory Glands)

Seminiferous Tubules

Coiled tubules located in the testes and are the site of sperm production

Sperm Production

Produced in the process of meiosis, occurring in the seminiferous tubules; millions created daily

Epididymis

Chamber sitting on top of each testis; site of sperm maturation and storage

Testis (Testes)

Site of gamete formation & testosterone production; located in scrotum

Vas Deferens

Tubes sperm travel up from the epididymis (during sexual activity) bringing the sperm to the prostate.

Ejaculatory Duct

Small tube "tunnel" that connects the Vas Deferens to the Prostatic Urethra.

Prostatic Urethra

Small portion of urethra passing through prostate gland and emptying into the penile urethra.

Penile Urethra

Tube that transports urine and semen from body by way of penis.

Accessory Glands

Seminal Vesicles, Prostate Glands, Cowpers/Bulbourethral Gland

Seminal Vesicles

Produces nutrient rich material "sack lunch," high in fructose (simple sugar), prostaglandins, and clotting proteins.

Fructose in Semen

Needed to make large quantities of ATP for energy to help the sperm cells swim.

Prostaglandins

Help cause muscular contraction of: smooth muscle of urethra aiding in ejaculation & muscle contraction in female tract aiding in movement of sperm through uterus and oviduct.

Clotting Proteins

Help the semen coagulate after ejaculation.

Prostate Gland

Provides the "red bull"; secretes slightly acidic solution, stimulating ATP production in sperm cell mitochondria; needed to have energy to swim through reproductive tract.

Bulbourethral Glands

Produce fluids before ejaculation; a slightly alkaline fluid "the shield," neutralizes the acid environment of penile urethra and acts as lubrication in penile urethra

Cowpers Gland

Same as the Bulbourethral Glands

Semen

Composed of millions of sperm cells with fluids from seminal vesicles, prostate, and bulbourethral (cowpers) glands.

Sex Hormone Production Beginning

Begins at puberty with hypothalamus; at puberty this part of the brain beings producing "releasing hormones" (GnRH or Gonadotropin Releasing Hormone)

Male Sex Hormone Production

GnRH travels to pituitary gland, causing the pituitary start producing FSH and LH. Once these reach testes, seminiferous tubules begin meiosis & producing sperm; also cause testes to start testosterone production.

Testosterone

Male sex hormone made by the testes; responsible for male secondary sex characteristics signaling growth in muscle, bone and cartilage. Also influences behavior/aggression.

Negative Feedback

the response reduces or shuts off the original stimulus; testosterone level stopping pituitary gland production of LH and FSH, while it is the pituitary glad that controls testosterone production through the testes.

Prostate Gland Location

Beneath the bladder, and the urethra passes through it

Norm Prostate Size

Size of a walnut until about the age of 50.

Abnormal Prostate Size

After 50, it will enlarge leading to restriction on the urethra causing difficulty urinating

Transurethral Resection

Used to treat enlarged prostate; resectoscope inserted into urethra --> electrical loop extended at prostatatic urethral --> this removes excess tissue, thus opening the urethral orifice

Prostate Cancer

Second most common form of cancer in men; Second most common cause of cancer death

Prostate Cancer Prevalence

Far more prevalent than lung cancer, death rate is much lower--due to early detection and slow rate of growth

Stages of Prostate Cancer

[A] few cancer cells [B] More cancer cells [C] Lots of cancer cells, starting to spread [D] Huge amount of c. cells, spreading

Spread of Prostate Cancer

Localized: Discomfort, not usually fatal--Metastasizes (breaks up and spreads): life-threatening, often spreading to lymph, and bones in the spine causing severe pain

Prostate Cancer Risk Factors

Increases with age (60-79 yrs at 1 in 7 risk); family hx, heritage (black men @ higher risk), and occupation (farmers) can have effects

Early Prostate Cancer Protection

Earlier prostate tumors are found, more successful surgery will be and better chances of survival

Detection of P.C.

Two primary ways are Digital Rectal Exam, and PSA test

Digital Rectal Exam

Start at age 40; MD feels for marble sized tumors. Advantages--inexpensive and available to all ; Disadvantages -- Cannot identify earliest stage (Stage A) b/c of tumor size

PSA

Prostate Specific Antigen test for protein in blood showing prostate changes, detecting only 80% of prostate cancers. MD looking for unusual changes (PSA increases with age normally). PSA increases also caused by ejaculation, hair growth meds.

Needle Biopsy

Attempting to dx at stage A. Biopsy gun inserted into rectum, [6-18] needle samples taken, analysis determines if cancerous and genetic analysis to identify cell type (Gleason Scale).

Prostate Surgery

Two types: Radical Prostatectomy-- the removal of entire gland OR Nerve-Sparing Prostatectomy-- leaves tissue near nerves

Side Effects of Surgeries

Incontinence: loss of bladder function & Impotence: i.e. ED

Radiation Treatments

2 types: Beam (high dose of radiation aimed at prostate cancer) and Radioactive Seed Implants (small pellets of radioactive material inserted into gland delivering treatment from inside the body. x2 the dose of Beam)

Radiation Pros and Cons

Pro: less recovery time, less likely to get ED -- Con: may not eliminate all c. cells, if radiation fails surgery not usually possible b/c of scarring of the tissue

Hormone Therapy

Drugs eliminate or block testosterone production, slowing or stopping tumor growth--side effects include feminization (menopausal SX'S), and cells are not removed or killed

Watchful Waiting

Recommended to men 75-80 b/c of possible slow prostate cancer growth (10+ yrs to be fatal) and treatment may not be worth it

Pathway of Unfertilized Egg

Follicle of ovary --> Oviduct --> Uterus --> Vagina

Ovary

Gamete (egg) produced here & hormone production. Thousands of follicles (nest of ovary cells) surround immature egg & produce estrogen. Each month, egg responds to reproductive hormones, matures, and is ovulated into oviduct

Oviduct

Aka Fallopian Tubes connect ovary to uterus -- is where egg is fertilized by sperm

Uterus

Muscular organ where blastocyst are implanted and development of fetus occurs

Blastocyst

Inner cell made up of undifferentiated stem cells

Endometrium

Inner layer of uterus, becomes vascular to prep for implantation of blastocyst. Layer is shed monthly when pregnancy doesn't occur.

Cervix

"Neck" of uterus extending into vaginal canal. Sperm swim through it to enter uterus & baby exits through cervix.

Vagina

Muscular tube that receives penis, site of sperm deposit, and serves as birth canal

Menstrual Cycle

Cyclic buildup and breakdown of endometrium as uterus prepares for monthly blastocyst [Declines with time]

Female Sex Hormone Production

FSH causes cells around 1 early stage ovum (called follicle) to grow and produce estrogen causing female sex characteristics & endometrium preparation. LH causes the follicle (w/ egg inside) to rupture and egg is released. After ovulation, "old" follicle produces progesterone, causing endometirum to be maintained

Preggo Calender

unsafe sex can lead to pregnancy from the 10th day of the month to the 17th day--few women are regular so this is only estimate

Ovulation begins...

fourteen days after menstration begins; fertilization happens around that time

Ovulation

The rupturing of mature follicle in response to LH from pituitary gland.

Corpus Luteum

A follicle after it goes through ovulation; produces progesterone which regulates the uterine lining in case of preg. Shift from follicle to corpus luteum happens during each 28 day cycle from puberty to meno.

Fertilized Egg Cycle

Implants in endometrium --> Embryo produces and sends out hormonal message (HCG) to corpus luteum signaling embryo is present --> Corpus luteum continues to produce progesterone and estrogen to maintain endometrium

Zygote

Egg after fertilization

Cleavage Division

Special type of mitosis; during division cell mass doesn't enlarge but # of cells increase, each being smaller than original, & continues till it takes on hollow ball form called blastocyst.

If Egg NOT Fertilized

Egg doesn't implant --> HCG not sent, thus stopping of progesterone and estrogen production --> without estrogen and progesterone, endometrium is shed --> menstrual cycle happens

Menopause

In woman's 40's, estrogen production declines --> Early signs/SX's of meno and may last for 5 yrs --> Estrogen production eventually stops, mentrual cycle stops and woman enters meno (actual meno is 12 consecutive months of no mentrual flow--usually 45-55)

SX'S of Meno

Hot flashes, dry skin, brittle hair, insomnia, vaginal dryness, mood swings, and skipped periods

Hormone Level Change W/ Meno

Uneven rise and fall of hormone lvls during perimenopause may be responsible for menstrual irregularities and other problems.

Osteoporosis

Bone thinning disease making it easy to fracture bones

Hormone Replacement Therapy Hx

1960's -- Women over 50 recommended to begin estrogen therapy to remove meno SX's
1970's -- Discovered estrogen alone increased chance of endomtrial cancer
1980's & 1990's -- Correlative studies suggested women who took estrogen post-meno less likely to have M.I. MD's recommend estrogen therapy combined with progesterone to prevent endometrial cancer
2002 -- WHI showed HRT increased risk of m.i., strokes, and clots, and breast cancer.
2010 -- Research suggest taking estrogen good for women in 50's but not older

Heart Disease

Kills x6 more women in post-meno than breast cancer making it #1 killer of women

Correlation v. Causation

Women who took HRT may have more $, better healthcare/more health conscious. HRT make women healthier, or were healthy women more likely to take HRT

Women's Health Initiative (WHI)

Study of thousands of women looking @ HRT effects in a two group experimental design (woman on HRT and placebo)

4 Estrogen Do's and Don'ts

DO - Use estrogen prn for hot flashes, night sweats, and other SX's
DON'T take it to prevent heart disease, osteoporosis, or other chronic conditions
DO use estrogen in smallest dose possible for minimum amount of time
DO take it with progesterone unless you have had a hyst.

Human Sexual Response

Men and women have very different sexual responses, the largest difference is the refractory period during which males aren't responsive to sexual stimulation.

Sexual Dysfunction: Men

Premature ejaculation, ED, low sexual desire

Sexual Dysfunction: Women

Low sexual desire, Arousal problems, Pain during intercourse

Painful Intercourse

Problems decrease with age; lowest in married women and slightly higher in women who never marry

Absence of Orgasm

Women have greater problem with reaching climax, problem decreases slightly w/ age

Male Sexual Stimulation

Includes hearing, sight, touch, psyche, and smell & is the result in nerve transmission from the brain to the penis effecting cyclic GMP levels in penis. It is INCREASED cyclic GMP levels that cause an erection to occur

Cyclic GMP

Enzyme causing relaxation of muscles in walls of blood vessels in penis --> muscles relax and more blood can flow into penis --> erection

Physiology of Erection

Stimulation increases cyclic GMP in penis and relaxation of smooth muscle --> Increased blood flow into erectile tissue --> Veins carrying blood are shut off --> Blood is trapped in erectile tissue

Loss of Erection Cycle

Lack of sexual stimuli leads to breakdown of cyclic GMP by PDE5 --> Decreased blood flow into erectile tissue --> Blood no longer trapped in tissue

PDE5

Another enzyme in penis that breaks down cyclic GMP to make the penis flaccid.

Erectile Dysfunction

Inability to achieve erection, possibly caused by not enough cyclic GMP--It is the 2nd most common sexual dysfunction and is not common in younger men. 80% of men 70+ have ED.

Pre-Viagra Treatments

Vacuum pumps, penile implants, gel suppositories in urethra, and shots into penis.

Vacuum Pumps

Involves use of vacuum to pull more blood into the erectile issue

Penile Implants

Inserted into the erectile tissue that could be "pumped up" when erection is desired

How ED Drugs Work

Allow stimulation to increase cyclic GMP by SUPPRESSING PDE5--> Increased blood flow into erectile tissue --> Veins carrying blood out are shut off --> Blood trapped in Erectile tissue

Viagra

PDE5 Inhibitor that blocks the activity of PDE5 allowing for more cyclic GMP to ACCUMULATE. It does NOT produce more cyclic GMP

Side Effects of ED Drugs

HA, Upset Stomach, Runny or Stuffy nose, Priapism

Priapism

An erection that does not end when sexual stimulation ends, and may last for hours damaging the tissue contributing to ED.

ED Drug Discovery

First examined as a drug to help w/ heart problems, but it didn't work. Test subjects would not return the pills, this ED drugs discovered to be awesome.

When Abortions Occur

Usually in pregnancy b4 15 wks

Types of Abortion

D&C, Suction, and RU486

D&C

Cervix is dilated, and embryo is scraped off endometrium

Suction

cervix dilated and suction tube used to remove embryo

RU486

pill is taken that interferes with maintenance of endometrium

How RU486 Works

Normally progesterone is necessary for implantation of fertilized egg, but RU486 blocks the action of preogesterone. Prostaglandins are taken to cause uterine contractions.

The "pill" (oral contraceptives)

Combo of synthetic estrogen and pregesterone hormones, stops ovulation preventing the ovaries from releasing eggs, also thickens cervical mucus making it harder for sperm to enter the uterus

The Morning After Pill

Post-Coital pill can be taken up to 72 hours after unprotected sex & scientist are not sure how it works. It may: stop ovulation, stop implantation, stop pregnancy from proceeding.

Human Development Involves

The addition of more cells through mitosis, creation of adult cells with special functions through cell differentiation creating about 210 different tissues in the body.

Mitosis of Body Cells

Prior to mitosis is replication of 46 chromosomes forms 46 replicated pairs. Splitting of replicated chromosomes forms two daughter cells with 46 chromosomes like the original cell.

Life Cycle of Humans Terms

Meiosis -- process of cutting chromosomes in half while in the body. [you have 23 chromosomes per sperm and egg]
Fertilized egg (Zygote) has 23 chromosomes from sperm AND egg, making 46.

Cell Differentiation

DNA directs changes in cells from general cell type (embryonic stem cells) to specialized cell types in the adult. It's hierarchical and once a cell moves from general to specific, it cannot change paths.

Stem Cells

Non-specialized cells that can be differentiate into other specific cell types; there are two kinds--embryonic and adult

Embryonic Stem Cells

Have the most potential for differentiation and can become nearly any type of cell in the body.

Adult Stem Cell

Usually can become only a particular type of cell because it has already started on a "specific path" in cell differentiation.

Embryonic Stem Cell Location

In the blastocyst (4-5 days after fertilization) and contains 50-150 cells

Adult Stem Cell Location

These are responsible for tissue repair and regeneration; birth = adult; found throughout the body; cells constantly die and must be replaced; these are not as flexible as embryonic

Adult Stem Cell Treatment

Bone marrow transplants (stem cells in bone marrow make new blood cells) and umbilical cord blood (banking cord blood, its almost as flexible as embryonic stem cells and could be needed in future)

Infertility in Women Causes

Hormone imbalance, blocked fallopian tube, ovarian cysts, endometriosis, uterine cysts

Infertility in Men Causes

Low sperm count, weak sperm, ED, hormone imbalance, medical side effects

In Vitro Fertilization

Eggs are retrieved from the ovary and fertilized in a dish. The embryos are then introduced into the uterus.

Louise Brown

First test tube baby

IVF Embryos

Hundreds of thousand embryos created via IVF and stored in liquid nitrogen tanks. Couples can use, donate, discard, or allow them to be used to stem cell research.

Treatment of Spinal Injuries

253k have spinal cord injuries, w/ 11k more each yr.

Rats were partially paralyzed, then injected with human embryonic stem sells and several weeks later they could walk again.

Dr. James Thomson

University of Wisconsin who in 1998 collected surplus embryos created at fertility clinics. Stopped the cells from differentiating, and kept them alive and reproducing.

Stem Cell Controversy

Fertilized egg from IVF is: 2-3 days old, only 8 cells, one cell can be removed and cultured as stem cells LEAVING the remaining to divide and develop normally.

Initial Stem Cell Research

used frozen embryos that were not going o be used for IVF, but discarded

Reprogramming Stem Cells

We can now reprogram adult stem cells to behave like embryonic -- Discovered by Dr. Thomson who can now make stem cells out of normal skin cells

Ban on Stem Cells

2001- Bush banned use of federal funds for stem cell research, except on cell lines already cultured in labs

The Original Lines

71 total, 65 proved useless with only 6 that remain useful to stem cell research

Federal Funding Argument

Stem cells offer hope to cure diseases, and federal funding drives the speed of research progress. Without it, the US could slip behind in the biotechnology race.

Obama's Permission

Obama has signed an executive order permitting federal funding for human embryonic stem cell research

DNA (Cookbook)

Each person has unique DNA which causes each person to have a unique complement of proteins which contributes too each person having unique appearance and behavior.
DNA IS NOT A PROTEIN, it's the instructions for making proteins

Life Cycle of Humans

Meiosis to produce sperm/egg --> fertilization and cleavage --> a zygote --> mitosis and cell differentiation --> a baby

DNA & Chromosomes

Chromosomes are a dense mass of DNA and some associated proteins. Each has specific genes, most genes code for the production of specific proteins.

23 Pairs or 46 Total

Number of chromosomes in a human cell.

# Different Proteins

Humans are made of up to 2 million different types of protein.

Protein Functions

Structural (hair, muscle) Chemical (antibodies, hormones, enzymes)

Enzymes regulate...

all chemical reactions in a cell.

Amino Acid Chains

These are what proteins are made up of, usually a few hundred amino acids long.

Protein Structure

is more than simply a chain of amino acids--to function properly, different proteins take different shapes

# of Different Amino Acids

20

Identity and Function of Protein

depend on the amino acid sequence and folding

Sickle Cell v. Normal Hemoglobin

The addition of valine, only one variation to the amino acid chain results in sickle cell anemia

Getting Amino Acids

11/20 can be made by the body -- 9/20 cannot.

Essential Amino Acids

the nine amino acids that cannot be made by the body and much be received via diet qd.

Gregor Mendel

Genetics was born in 1866 this monk who published a paper defining "gene" as the unit that passes down heritable traits. Argued kids get 2 copies of each gene--one from father and mother.

DNA Structure Discovery

Discoved in 1950's by Watson, Crick, Wilkins, and Franklin

Double Helix

The twisted latter shape of DNA

Nucleotides

The building blocks of DNA that cause the DNA to twist in structure.

# of Nucleotides

4 total

Nucleotide Coding

3 nucleotides code for one amino acid [different codes of nucleotides code for different amino acids.

DNA & Protein

DNA in the chromosomes of the nucleus determine the protein synthesis made at ribosomes.

Protein Synthesis

"The Central Dogma"
DNA uncoils and 1 strand is used to produce mRNA in nucleus --> mRNA leaves nucleus and goes to ribosomes with recipe --> amino acids linked together according to nucleotide recipe of mRNA

RNAi

The "cop" which reads detects any mRNA that does not belong to the system. If it finds one, it destroys all of the mRNA containing the similar sequence and the production of that protein stops.

Human Genome Project

Defined as sum total of genes in a human, estimating 2o-25k genes in each human controlling protein production.

Three billion nucleotides

is the total number per human cell.

Average # of bases per gene

Several thousand

Human Genome Facts

a] began in late 1980's supported by 15 billion b] sequenced rought 3 billion chemical letters in DNA that comprise the genetic code for humans c] completed in 2000

DNA Frontiers

-Figure out what the Junk DNA does accounting for 99% of DNA.
-Sequence of letters in DNA for the human gnome is known, but gene-protein relationship unknown
-Learning about molecular switches regulating how DNA guides protein synthesis.

Alleles

These are the specific expression of each gene and every pair of chromosomes has the same GENES but the alleles on each member may be different.

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