Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

Hormones, Sex and Sexual Behaviors :))

No description
by

Sarah Jane Caparoso

on 11 September 2012

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Hormones, Sex and Sexual Behaviors :))

•Chemical messengers secreted by endocrine glands; responsible for specific regulatory effects on certain part of organs. Hormones •Chemical substances, secreted by cells into the extra cellular fluids, which regulate the metabolic activity of other cells in the body. •Comes from the Greek word “to arouse” Regulates longer term metabolic processes
Properties of the
Endocrine System Hormones act on target cells Release regulated by negative feedback Hormones alter metabolism of many cells Hormones are chemicals Releases hormones from endocrine cells Shares some features with nervous system 1.Hypothalamus – Production of antidiuretic hormones (ADH), Oxcytocin and
Regulatory hormones Organs and
Hormones b.Ovaries (female) – Estrogen, progestin, inhibin a.Testes (male) – Androgen (testosterone),inhibin 12.Gonads 11.Pancreatic Islets – Insulin, glucagons 10.Adipose Tissue – Leptin, Resistin 9.Kidney – Renin; Erhthropoietin (EPO); Calcitonin 8.Heart – Atrial natriuretic peptide (ANP) 7.Parathyroid glands – Parathyrooid hormone (PTH) 6.Pineal Gland – Melatonin b.Adrenal cortex – Cortisol, corticosterone, aldosterone, androgen a.Adrenal medulla – Epinephrine and Norepinephrine 5.Adrenal Glands 4.Thymus – undergo atrophy during adulthood – Thymosins 3.Thyroid Gland – Thyroxine (T4); Triiodothyronine (T3); Calcitonin (CT) b.Posterior Pituitary – Release of oxcytocin and antidiuretic hormone (ADH) a.Anterior Pituitary – adenocorticotrophic hormone (ACTH); Thyroid Stimulating hormone (TSH);Gonadotrophic Hormone (GH); Follicle stimulating hormones (FSH); Luteinizing hormones (LH). 2.Pituitary gland – Structure of Hormones •Three chemical families •Hormone receptor – A protein in a cell membrane, or within the cytoplasm or nucleus, to which a hormone specifically binds to trigger its actions on a target cell. •Target Cells – Peripheral cells that can respond to a particular hormone Lipid derivatives – steroids (e.g., testosterone); Elcosanoids (e.g.,prostaglandins) Peptides and Proteins – chains of amino acids E.g., insulin, ADH Amino acid derivatives – E.g., epinephrine, thyroid hormones Extracellular Receptors – Located in cell membrane Classes of Hormone Receptor - Thyroid hormones also act on mitochondria - Operates trough changes in gene expression - Targeted by steroid and thyroid hormones - Located in cytoplasm or nucleus Intracellular Receptors - Operates through a second messenger such as cyclic AMP - Targeted by: Amino acid derivatives; Peptides; Eicosanoids •Hormones directly enter capillaries Hormone Secretion and Distribution Breakdown by extracellular enzymes Removal by liver, kidney cells Binding to cell receptor •Hormones are in activated by: Steroid, thyroid hormones bind to blood proteins for transport Most hormone travel free in solution •Distributed widely in the circulation Sex hormones Hormones and Behavior Leads to feeling of thirst, water intake Antidiuretic hormone Deficiency leads to sluggishness Excess leads to nervousness, restlessness Thyroid hormones Estrogen fosters sexual receptivity Testosterone fosters aggressiveness Hormones and Aging Many hormones unaffected by age •Tissue response to ADH, glucocorticoids declines Leads to loss of bone density, muscles mass Insulin release reduced Reduced or absent reproductive hormones For some people it’s only penis-in-vagina intercourse. For some people, it’s only penis-in-anus intercourse (anal sex). For some people, it’s genital rubbing without intercourse. For some people, it includes oral / genital contact. For some, it includes masturbation. The possibilities are many. For most experts (like Merriam-Webster and us), it includes all of the above. What is sex??? People define “sex” in different ways. The Merriam-Webster dictionary defines it as “sexually motivated behavior.” This sounds right to us. But not everyone agrees with the dictionary or with us. People all have their own definitions of what “sex” and “having sex” means. However you define it, being sexual with another person — whether that means kissing, touching, or intercourse — involves a lot of responsibility. It’s very important to protect yourself against pregnancy and sexually transmitted infections. And you need to make decisions about protection before you engage in vaginal, anal, or oral sex. When do people start
having sex??? It depends. The average age when people start having sex is about 17. Only about half of high school students have ever had intercourse and even once they start having sex, most teens don't have sex frequently. Choosing to have sex is a big decision. It's important to wait until you're ready to have sex. You may feel flushed or warm, your heartbeat will race, you will breathe harder, and you'll experience rapid muscle spasms mainly concentrated in the genital and anal areas. What’s an orgasm? How can I
tell if I've had one? An orgasm is the release of built-up muscle tension resulting from sexual activity. It produces rapid muscle contractions usually in the genital and anal area, but these contractions can also be throughout the whole body. Most people find these muscular contractions very pleasant. At the same time, painkilling chemicals called endorphins are released into the bloodstream, causing intense pleasure and relaxation. In both men and some women, an orgasm is often accompanied with the release of ejaculatory fluid. Ejaculation is much more usual in men than it is in women. Only about 10 percent of women report ejaculating during orgasm. Orgasms can be reached through many different types of sexual activity. Most women are more likely to reach orgasm through clitoral stimulation rather than stimulation of only the vagina. Men tend to reach orgasm more quickly than women, just as men tend to become sexually aroused more quickly than women. On the other hand, women are more likely to have more than one or multiple orgasms during sexual activity than men are. Women’s experience with orgasm is more varied than men’s, and not all women experience orgasm in the same way. There are also many women and men who get great pleasure from sex, whether or not they have orgasms. NO.. Most women's vaginas are between three and seven inches long. This usually depends on a woman's general body stature. However, the vagina can stretch much longer and wider during sexual intercourse or childbirth. It is true, however, that some penises are too big to fit comfortably in some vaginas. This is one of the disadvantages of having a very big penis. Is it possible for a penis to go too far
into a vagina? Oral sex is using one's mouth to stimulate a partner's genitals. What is oral sex? Just as with any kind of sex, everybody is different — with various likes and dislikes, so communication is the key. In order to make sex more satisfying, it's important to be clear with yourself and your partner about what kinds of sex you want to do and don't want to do. Learning how to give oral sex is usually done by letting each other know what feels good and what doesn't — so both partners can learn what’s pleasurable. Although there is no chance for pregnancy to happen from oral sex, unprotected oral sex puts both partners at risk for a number of sexually transmitted infections, whether they are giving or receiving genital stimulation. Although the risks of infection are generally quite a bit lower with unprotected oral sex than they are with unprotected vaginal or anal intercourse, using a barrier during oral sex can further decrease those risks. For safer oral sex, use a condom to cover the penis, or a Sheer Glyde dam, cut-open condom, or plastic wrap to cover the vulva or anus. No, it's not possible to become pregnant from oral sex whether ejaculate is swallowed or not. But pregnancy can occur if sperm are spilled into the vagina or on the vulva during any kind of sex. Can I get pregnant from oral sex? However, unprotected oral sex — on a woman or on a man — puts both partners at risk for a number of sexually transmitted infections, whether they are giving or receiving genital stimulation. For safer oral sex, use a condom to cover the penis, or a Sheer Glyde dam or plastic wrap to cover the vulva or anus. It’s not possible to become pregnant from anal sex (inserting the penis into the anus). But pregnancy can occur if semen if spilled into the vagina or on the vulva during any kind of sex. How safe is anal sex? Can I get pregnant from anal sex? Like unprotected vaginal intercourse, unprotected anal intercourse is high-risk for many sexually transmitted infections. Use condoms during anal sex to decrease the risk of sexually transmitted infections. Some men and women enjoy anal sex, and others do not. Anal sex can hurt if partners do not take certain steps. The anus does not usually produce enough lubrication for comfortable anal sex, so it is important to use an artificial water-based lubricant — like K-Y jelly or Astroglide — for anal sex. (Using an oil-based lubricant, like Vaseline, can damage latex condoms.) Does anal sex hurt? It’s also important to stop doing it if anything hurts and communicate with your partner about how you feel — sex that’s painful or uncomfortable should not continue. Not all people enjoy anal intercourse. Those who don't enjoy it should not be embarrassed into it and should not force themselves to accept it. Many people feel this way at various times in their lives. It’s perfectly normal. People have different levels of sexual desire — some have more and some have less. Some people would be happy to have sex every day, and some people would be happy to have sex once a month, or less often, or not at all. What if I don’t want to have sex with anyone, ever? Many things can affect our desire for sex. They include stress, hormones, how comfortable we are with our partners, past sexual experiences, if we feel safe, how much we’re attracted to someone, illness, medication, and many other factors in our lives.different ways. The Merriam-Webster dictionary defines it as “sexually motivated behavior.” This sounds right to us. But not everyone agrees with the dictionary or with us. People all have their own definitions of what “sex” and “having sex” means. For some people it’s only penis-in-vagina intercourse. For some people, it’s only penis-in-anus intercourse (anal sex). For some people, it’s genital rubbing without intercourse. For some people, it includes oral / genital contact. For some, it includes masturbation. The possibilities are many. For most experts (like Merriam-Webster and us), it includes all of the above. However you define it, being sexual with another person — whether that means kissing, touching, or intercourse — involves a lot of responsibility. It’s very important to protect yourself against pregnancy and sexually transmitted infections. And you need to make decisions about protection before you engage in vaginal, anal, or oral sex When do people start having sex? myths and facts about sex When it comes to having sex, many teens — and adults too — have trouble separating fact from mythology. Here are some common myths and facts about having sex. Collapse All - The myth is that only vaginal intercourse counts as having sex. In fact, there is no one definition of "having sex." For some people sex is penis-in-vagina intercourse. For some people, sex is penis-in-anus intercourse. For some people, sex is intercourse with a sex toy. For some people, sex is genital rubbing without intercourse. For some people, sex includes oral/genital contact. For some, sex includes masturbation. The possibilities are many. For most experts (like us), it includes all of the above. Does oral sex count as sex? People decide for themselves what it means to them to "have sex." To avoid confusion when talking about having sex with sex partners, it’s important to clearly communicate your limits and expectations and to be sure you understand theirs. The myth is that most teens have had vaginal intercourse. Surprise, surprise: most haven’t! The truth is that only about half of high school students have ever had intercourse and the average age when people start having sex is about age 17. Even once they start having sex, most teens don't have sex frequently. So it's "normal" to wait until you're older to have sex. Are most teens having vaginal intercourse? Can I get pregnant the first time I have sexual intercourse? Can I get pregnant if I don’t have it that often? The myth is that a girl cannot get pregnant the first time she has vaginal intercourse. This is not true. If you’re having unprotected intercourse you can get pregnant — whether it is the first time or the one hundred and first time! It’s even possible for a girl to get pregnant before she has her first period — this is because an egg is released before menstruation can happen. It’s also possible to get pregnant whether you have intercourse often or only once in a while. It's all about the sperm hooking up with the egg. If that happens, pregnancy can occur. So if you’re sexually active, it's important to use birth control if you don't want to get pregnant. The myth is that a doctor, or anyone else who looks at woman’s vulva, can tell if she’s a virgin. This isn't true. Even pelvic exams can't reveal if you've had vaginal intercourse or if you masturbate, unless there are specific signs. A health care provider may be able to tell a woman is not a virgin if she has Can a doctor tell if I’m a virgin? So usually, the only way a nurse or doctor will know if a woman's had sex is if the woman tells her. It's important to be honest with health care providers so they can get an accurate picture of your health and needs. It can help health care providers so they can determine if it's a good idea to test for sexually transmitted infections, prescribe birth control, recognize pregnancy symptoms, or talk with clients who have problems with their sexual relationship. The myth is that it is impossible for a woman to get pregnant from vaginal intercourse during her period. It's not likely for most women, but it can happen. It’s possible for a woman to get pregnant from intercourse during her period, especially if her menstrual cycle is brief or irregular. Can I get pregnant if I have sex when
I’m having my period? And of course, another important concern of having unprotected intercourse — anytime during the month — is that it offers no protection against sexually transmitted infections. The myth started by opponents of birth control is that condoms don’t really work. The fact is that, when used correctly every time, condoms are 98 percent effective in preventing pregnancy. And condoms are the best way to avoid sexually transmitted infections for people who are sexually active. Most breakage happens because condoms are used incorrectly. In fact, properly lubricating a condom helps reduce the likelihood of the condom breaking. However, only water- or silicone-based lubricants such as KY jelly, Astro Glide, Slippery Stuff, etc., can be used with latex condoms. Do condoms really work? Sexual Behavior refers to the manner in which humans experience and express their sexuality. Sexual Behavior Mostly girls and boys living in Western countries experience their first feelings of sexual attraction at about 13 years of age. Sexual interest is triggered by puberty, which, as you have learned, currently tends to occur at adolescence. Does age matter when it comes to sex? 1. protein hormones and peptide hormones- are chains of amino acids. Peptide hormones are short chains, and protein hormones are long chains.

2. steroid hormones- are hormones that are synthesized from cholesterol, a type of fat molecule.

3. sex hormones: estrogens, progesterone, and androgens

- are actually steroids

- can react with receptors on cell membrane

-sometimes increase number of dendrite 3 Types of Hormones • attach to a receptor that turns a gene on or off

• called sex-limited genes because effect is much stronger in one sex that in the other

(eg: breast development gene) produce small amounts of the male hormones - testosterone and androgens.
• The fact that adult ovaries tend to release more estrogens than they do androgens and that adult testes Spines - Adult Ovaries produce large amounts of the female sex hormones-estrogen and progesterone. What Hormones responsible when it comes to sexual behavior ? - They also release more androgens than they do estrogens. Both men and women also have two important hormones, both secreted by the pituitary gland, called FSH and LH. • Sexual Behavior is influenced by gonadol hormones acting on the brain by the neural connections of the hypothalamus. • The level of progesterone rises sharply after ovulation, and then falls off just before the period. • The level of estrogen rises slowly during the first half of the month, often dips sharply at ovulation - which occurs around about day 14 - and gradually falls off just before the period. Day one of our cycle is the first day of a period. In a monthly cycle, two main things happen: • LH (which stands for luteinising hormone) controls the production of sex hormones by the ovaries. A Swiss gynaecologist (see below) told us that he believes LH is strongly linked to desire. • FSH (which stands for follicle stimulating hormone) controls the formation of eggs by the ovary. NEURAL CONTROL OF SEXUAL BEHAVIOR IN FEMALES • ventromedial nucleus of the hypothalamus - most critical for performance of female sexual behavior

- lesions in female rats result in no lordosis, even with hormonal treatment

- electrical stimulation facilitates female sexual behavior

- estradiol followed by progesterone activates sexual behavior of female rats

- estradiol increases production of progesterone receptors

• periaqueductal gray matter - receives info from VMH, and sends axons to reticular formation of medulla and then to spinal cord

- lesions disrupt lordosis, electrical stimulation facilitates it

- lesions disconnecting PAG from VMH disrupt female sexual behavior

• neurotransmitters

- oxytocin - after estradiol and progesterone, injections into VMH facilitate lordosis

- norepinephrine - vaginal stimulation increases activity of noradrenergic neurons 1) spinal nucleus of the bulbocavernosus - in ventral horn of lumbar region of spinal cord of rats
contains motor neurons that innervate muscle attached to base of penis and involved in sexual activity
this muscle is not present in female rats
if female rats are injected with testosterone on 2nd day after birth, they develop this nucleus
if male rats treated prenatally by androgen-inhibiting drugs and then castrated after birth, they don’t develop this nucleus
direct effect - androgens prevent deterioration of this nucleus during the first 10 days after birth
indirect effect - androgens make male rat pup urine attractive to their mothers, causing them to lick the anogenital region; if mothers fail to do so (no sense of smell), then 11% fewer neurons in the SNB

2) medial preoptic area - forebrain region most critical for male sexual behavior
some neurons of the MPA appear to play a role in motivation, not copulatory behaviors
sexually dimorphic nucleus - within MPA of rat
3-7 times larger in males than females
size controlled by amount of prenatal androgen exposure
volume directly related to the animal’s level of sexual activity
lesions decrease masculine sexual behavior

NEURAL CONTROL OF SEXUAL BEHAVIOR IN MALES • during puberty, cells in hypothalamus secrete gonadotropin-releasing hormone, which stimulates the production and release of two gonadotropic hormones by the anterior pituitary gland: - follicle-stimulating hormone
- luteinizing hormone DEVELOPMENT OF SECONDARY
SEX CHARACTERISTICS • these stimulate gonads to produce their hormones, which lead to secondary sex characteristics: - estradiol , type of estrogen, produced by ovaries, which also produce small amount of testosterone

- testosterone produced by testes, which also produce small amount of estradiol • aromatization - testosterone converted to estradiol by enzyme, aromatase; thus, testosterone can have an effect on estrogen receptors in cells
• oxytocin - produced by posterior pituitary gland, released during orgasm, contributing to muscular contractions; may play a role in sexual satiety and social bonding
• prolactin - secreted by anterior pituitary gland; promotes milk production in females and has inhibitory effect on male sexual behavior
• remember, "nature’s impulse is to create a female" HORMONAL CONTROL OF
SEXUAL BEHAVIOR •Pituitary Gland

- anterior pituitary: endocrine gland

•synthesizes six hormones that control other glands

•controlled by the hypothalamus

- posterior pituitary or neurohypophisis: neural

connection

•half gland half nucleus

•connected to the hypothalamus

•produces releasing hormones which flow through the blood to the anterior pituitary. Control of Hormone Release Thank You! :)) Hormones, Sex and
Sexual Behavior Hormones SEX 3) medial amygdala - receives info from olfactory bulbs and vomeronasal organ
damage to this area disrupts many effects of pheromones
one region with many androgen receptors is 85% larger in male vs. female rats
destruction of medial amygdala disrupts sexual behavior of male rats
in humans, temporal lobe seizures often associated with hyposexuality
neurotransmitters
oxytocin - transmitter substance in brain, involved in erection and ejaculation
vasopressin - also serves as transmitter substance in brain, positively correlated with male sexual behavior
odopamine - medial preoptic area
Full transcript