Marinas-Science-10-Unit-3: Living Things and Their Environment PDF

UNIT III – LIVING THINGS AND THEIR ENVIRONMENT Prepared by: Jesa Marie J. Mariñas Coordinated Functions of the Reproductive, Endocrine, and Nervous Systems REPRODUCTIVE SYSTEM Male And Female Reproductive System: Parts and Functions MALE ▪ Is network of external and i...

UNIT III – LIVING THINGS AND THEIR ENVIRONMENT Prepared by: Jesa Marie J. Mariñas Coordinated Functions of the Reproductive, Endocrine, and Nervous Systems REPRODUCTIVE SYSTEM Male And Female Reproductive System: Parts and Functions MALE ▪ Is network of external and internal organs that function REPRODUCTIVE to produce, support, SYSTEM transport, and deliver viable sperm for reproduction. PARTS OF THE ▪ Penis. The primary organ for sexual intercourse and urination. It consists of MALE three parts: the root (anchored to the REPRODUCTIVE pelvic floor), the body (shaft), and the glans (tip). SYSTEM ▪ Scrotum. A fibromuscular sac that houses the testes and maintains an optimal temperature for sperm production through thermoregulation. ▪ Testes. Oval-shaped glands located within the scrotum. They are responsible for producing sperm through spermatogenesis in the seminiferous tubules. PARTS OF THE ▪ Seminiferous tubules. Large coiled MALE tubes that are the chief site for production of sperm. REPRODUCTIVE ▪ Epididymis. A coiled tube attached to SYSTEM each testicle, where sperm mature and are stored until ejaculation. ▪ Ductus (Vas) deferens. A muscular tube that transports mature sperm from the epididymis to the ejaculatory ducts during ejaculation. PARTS OF THE ▪ Seminal vesicles. Produce a MALE fructose-rich fluid that nourishes the sperm and contributes to semen REPRODUCTIVE volume. SYSTEM: ▪ Prostate gland. Adds enzymes and ACCESSORY GLANDS citric acid to semen, maintaining its fluidity and supporting sperm viability. ▪ Bulbourethral (Cowper's) glands. Secrete a clear mucus that lubricates the urethra and neutralizes residual acidity from urine. ▪ The testes (singular: testis) are the primary reproductive organs in males. ▪ The testes begin to produce sperm when males reach puberty. ▪ Adult males produces several hundred million sperm cells each day. ▪ After sperm is produced in the testis; it enters the epididymis where it is stored until maturity. Mature sperm then travels from the epididymis to the vas deferens. It exits the body through the urethra during ejaculation. THE HUMAN SPERM CELL Is the male reproductive cell and has three (3) parts: 1. Head. Made up of a nucleus covered by a cap called acrosome which stores the enzymes needed to penetrate the egg cell. 2. Midpiece. Contains the mitochondria that supply the energy needed to propel the sperm through the female reproductive tract. 3. Tail. Powerful flagellum that enables the sperm to move. MALE HORMONES AND FUNCTIONS ▪ Luteinizing Hormones (LH). Secreted by the anterior pituitary gland. It stimulates the production of the sex hormone, testosterone. ▪ Follicle-Stimulating Hormone (FSH). Also secreted by the anterior pituitary gland. It stimulates sperm production in the seminiferous tubules. ▪ Testosterone. Produced by the Leydig cells. It is responsible for the development of secondary male characteristics during puberty such as deepening of the voice, growth of facial hair, broadening of shoulders, and increase in muscle mass. FEMALE ▪ includes parts of the female body that are involved in REPRODUCTIVE fertility, reproduction and SYSTEM sex. PARTS OF THE ▪ Ovaries. There are 2 ovaries, 1 on FEMALE each side of the uterus where female hormones (estrogen and REPRODUCTIVE progesterone) are produced, and SYSTEM eggs are stored to mature. ▪ Fallopian tubes. These are 2 thin tubes that connect the ovaries to the uterus, allowing the egg to travel to the uterus. PARTS OF THE ▪ Uterus. A hollow, pear-shaped organ that holds a fetus during pregnancy. The FEMALE lining of the uterus thickens with blood REPRODUCTIVE and other substances every month. SYSTEM ▪ Cervix. The lower part of the uterus that connects the uterus to the vagina. Prevents foreign article from entering the uterus. ▪ Vagina. A muscular tube connecting the cervix to the outside of the body. PARTS OF THE ▪ Vulva. Collective name used to refer to the external parts of the female FEMALE reproductive system. REPRODUCTIVE ✓Labia majora. Enclose and protect other SYSTEM external reproductive organs. ✓Labia minora. Lie just inside the labia majora surrounding the vaginal opening and urethra ✓Vaginal opening. Allows menstrual blood and babies during reproduction to exit the body. ✓Clitoris. A small sensitive protrusion were the labia minora meet. ▪ The onset of mature egg cell production among females starts around the ages of 11 to 14 years. ▪ Menarche refers to the first discharge of blood from the vagina. ▪ A normal adult female releases a mature egg cell from one of her ovaries every month. ▪ Gestation or pregnancy refers to the nourishment and protection of a fertilized egg during nine months of development. ▪ The onset of mature egg cell production among females starts around the ages of 11 to 14 years. ▪ Menarche refers to the first discharge of blood from the vagina. ▪ A normal adult female releases a mature egg cell from one of her ovaries every month. ▪ Gestation or pregnancy refers to the nourishment and protection of a fertilized egg during nine months of development. EGG PRODUCTION ▪ All females are born with approximately 2,000,000 eggs but only 400,000 of these will reach puberty. ▪ During puberty, the increased production of hormones enables one immature egg to complete its development each month. ▪ In the lifetime of a female, only 300 to 500 egg cells will reach maturity. ▪ Ova (singular: ovum) refers to matured egg cells released by the ovaries every month. ▪ It takes 3-4 days for the ovum to travel inside the fallopian tube. If the ovum is not fertilized, it dies within 24-48 hours. FEMALE REPRODUCTIVE CYCLES: THE OVARIAN CYCLE ▪ A series of changes that occur in the ovaries, preparing for ovulation and the release of an egg. It is regulated by hormones produced by the pituitary gland, hypothalamus, and ovaries. ▪ The ovarian cycle spans about 28 days, although it varies from female to female. ▪ Ovulation – The monthly release of ovum from the ovary. ▪ The ovarian cycle happens in two distinct phases: follicular and luteal. THE OVARIAN During this phase, hormones regulate the CYCLE: completion of an egg cel’s maturity. FOLLICULAR 1. The anterior pituitary gland releases gonadotropins follicle-stimulating PHASE hormones (FSH) and luteinizing hormones into the bloodstream. These hormones cause the follicles to produce estrogen. 2. Estrogen aids the growth of the ovarian follicle. When the follicle bursts, ovulation occurs. Egg cells mature within follicles inside the ovary. A follicle is a cluster of cells that surrounds an immature egg cell. THE OVARIAN After ovulation, the luteal phase begins. CYCLE: 1. Luteinizing hormones causes the cells LUTEAL PHASE of the ruptured follicle to grow forming corpus luteum. 2. LH causes the corpus luteum to secrete both estrogen and progesterone. Corpus luteum is a yellowish mass of follicular cells that functions like an endocrine gland. Progesterone is a sex hormone that signals the body to prepare for fertilization. FEMALE REPRODUCTIVE CYCLES: THE MENSTRUAL CYCLE ▪ The menstrual cycle is a term used to describe the sequence of events that occur in the body as it prepares for the possibility of pregnancy each month. The events in the cycle are controlled by the changing levels of estrogen and progesterone during the ovarian cycle. ▪ The menstrual cycle is the time from the first day of your menstrual period until the first day of your next menstrual period. Every person’s cycle is slightly different, but the process is the same. ▪ A normal menstrual cycle last for an average of 28 days. FEMALE REPRODUCTIVE CYCLES: THE MENSTRUAL CYCLE ▪ Prior to and after ovulation, increased levels of estrogen and progesterone cause the lining of the uterus to thicken. ▪ If pregnancy does not occur, the levels of progesterone decrease causing the lining of the uterus to shed, marking the end of the menstrual cycle. ▪ Menstruation is the monthly shedding of the lining of your uterus. A mixture of blood (from blood vessels breaking) and discarded tissues leaves the body through the vagina. FEMALE REPRODUCTIVE CYCLES ▪ At the end of the ovarian and menstrual cycles, neither estrogen nor progesterone is produced. This signals the pituitary gland to produce FSH and LH, starting the cycles again. ▪ The production of estrogen and progesterone in women eventually declines around mid-40s. This begins the transition to the menopausal stage when a woman no longer ovulates or becomes fertile. PREVENTION, DETECTION, AND TREATMENT OF SEXUALLY TRANSMITTED DISEASES GONORRHEA ▪ Caused by a sexually transmitted Symptoms: bacterium, Neisseria ▪ Burning sensation during urination, pain or gonorrhoeae swelling in one testicle, and a pus discharge ▪ The bacteria invades the from the urethral opening for the infected men. epithelial lining of the vagina and the male urethra which results ▪ Increased vaginal discharge, painful urination, into a discharge called pus. vaginal bleeding in between periods, and ▪ It can also affect the rectum, abdominal and pelvic pain for infected women. eyes, throat, and joints. ▪ Women usually do not experience any ▪ Gonorrhea can also affect babies symptoms in the early stages. born to an infected mother. SYPHILIS ▪ Is a sexually transmitted Symptoms and stages: disease cause by the bacterium Treponema 1. Chancre initially develops at the site of the pallidum. infection (e.g.: genitals, rectum, or mouth). ▪ Can be easily cured but can 2. Fever and a skin rash that begins in the trunk lead to serious complications if (may cove the entire body) occurs after several left untreated. weeks. If left untreated, it will disappear or may ▪ The disease has an incubation come and go within a year. period of a few weeks to 3. It will enter latent stage without symptoms. It several months and occurs in will lead to neural lesions causing extensive several stages before it turns damage to nervous tissues leading to paralysis, into a dangerous condition. mental disorder, or death. SYPHILIS ▪ Congenital syphilis can be contracted by babies from an infected mother. ▪ Symptoms experience by infected babies include deafness, tooth deformities, and collapse of the nose bridge. ▪ Antibiotics are used to treat the initial stages of syphilis to stop it from progressing. Longer cases may require higher dosage of antibiotics. GENITAL HERPES ▪ An infection caused by herpes Symptoms: simplex virus-2 (HSV-2). ▪ Characterized by painful, itching lesions and ▪ The virus may stay dormant in blister-like eruptions in the genital area that the body but may activate during stress and illness. occur 10 days after exposure to an infected sexual partner. ▪ It is incurable but can be managed by antiviral ▪ Sores take about two weeks to heal and may medications to help reduce the recur. severity and frequency of outbreaks and make it less ▪ Some infected individuals may not experience likely to spread the virus to signs and symptoms and yet may be others. contagious. AIDS ▪ Acquired Immunodeficiency Symptoms: Syndrome (AIDS) is caused by ▪ People living with HIV do not show symptoms in the virus, Human the early stage. It has a latency period of 5-10 Immunodeficiency Virus (HIV). years before symptoms are noticeable. ▪ This condition attacks the ▪ AIDS-related symptoms in the later stage include immune system of the infected weight loss associated with diarrhea, swollen person. lymph glands, chronic low-grade fever, fatigue, ▪ The first cause of AIDS was and night sweats. reported in 1981 and still ▪ In the last stages of AIDS, patient becomes persists today because no cure susceptible to pneumonia, tuberculosis, and other is available. opportunistic infections. AIDS ▪ There is no known cure for ▪ Isaac Asimov is one of the notable persons AIDS but a prompt medical who have died of complications due to AIDS. attention can reduce or delay ▪ He is a famous science fiction writer known for the onset of serious iRobot and the Bicentennial Man. complications. ▪ 10 years after his death it was revealed that his ▪ AIDS is transmitted through myocardial and renal complications were the contact with body fluids result of HIV infection he contracted through (semen, vaginal fluid, blood, HIV-contaminated blood transfusion. and breast milk). ENDOCRINE SYSTEM Glands, Function, and Hormones  ENDOCRINE SYSTEM ▪ Consists of glands that produce hormones to control the bodies normal functioning. It influence reproduction, metabolism, growth and many other functions. ▪ Glands. An organ whose cells secrete chemical signals that are delivered to the different regions of the body. ▪ Endocrine Glands. Ductless glands that secrete hormones directly into either the bloodstream or the fluid around the cells (endo means within; krinein means separate) ▪ Hormones. Chemical messengers that carry instructions to cells to change their activities. GLANDS OF THE ▪ Hypothalamus. An area in your brain that links the brain to the hormonal system. It is ENDOCRINE connected to the pituitary gland by a stalk. SYSTEM Some of the hormones released by the hypothalamus help control the pituitary gland. ▪ Pituitary gland. A small gland located at the base of the brain known as the master gland of the endocrine system. It stores and releases hormones created by the hypothalamus. The pituitary gland also controls many of the other endocrine glands: thyroid, adrenal, ovaries, and testes. GLANDS OF THE ▪ Thyroid gland. Located at the front portion of the neck. It releases hormones that ENDOCRINE influences metabolism, energy levels, body SYSTEM temperature, and calcium levels. ▪ Parathyroid glands. These are 4 small glands in the neck that regulate the calcium level in the blood. ▪ Adrenal glands. These glands sit on top of the kidneys. The adrenal glands influence the body’s stress response, blood pressure control, and metabolism. GLANDS OF THE ▪ Pineal gland. A very small gland near the center of the brain. It helps the circadian ENDOCRINE rhythm of the body. Also known as the SYSTEM body’s third eye. ▪ Pancreas. A long gland found behind the stomach under the liver. The main endocrine function of the pancreas is to regulate the blood sugar levels. ▪ Gonads. Glands that produce hormones that are involved in reproduction and other functions of the body. 1. Ovaries – found in women 2. Testes – found in men  ENDOCRINE GLANDS AND HORMONES RELEASED Gland Location Hormones Released ▪ growth hormone releasing hormone (GHRH) ▪ thyrotrophin releasing hormone (TRH) ▪ corticotrophin releasing hormone (CRH) Hypothalamus Brain; connected to the pituitary gland ▪ gonadotrophin releasing hormone (GnRH) ▪ oxytocin ▪ vasopressin ▪ dopamine ▪ somatostatin ▪ growth hormone (GH) ▪ thyroid stimulating hormone (TSH) ▪ adrenocorticotrophic hormone (ACTH) Pituitary Gland Base of the brain ▪ follicle stimulating hormone (FSH) ▪ luteinizing hormone (LH) ▪ Prolactin ▪ Oxytocin ▪ vasopressin  ENDOCRINE GLANDS AND HORMONES RELEASED Gland Location Hormones Released ▪ Tri-iodothyronine (T3) Thyroid Gland Front of the neck ▪ Thyroxine (T4) ▪ Calcitonine Parathyroid Glands Neck; back of the thyroid ▪ Parathyroid hormone (PTH) ▪ Adrenaline ▪ Cortisol Adrenal Glands On top of the kidneys ▪ Aldosterone ▪ Dehydroepiandrosterone (DHEA) ▪ Testosterone (in small amounts) Pineal Gland Near the center of the brain ▪ Melatonin ▪ Insulin ▪ Glucagon Pancreas Behind the stomach, under the liver ▪ Vasoactive intestinal peptide (VIP) ▪ Somatostatin  ENDOCRINE GLANDS AND HORMONES RELEASED Gland Location Hormones Released ▪ Oestrogen ▪ Progesterone Women; found in each side of the Ovaries ▪ Testosterone womb ▪ Anti-mullerian hormone (AMH) ▪ Inhibin A and Inhibin B ▪ Testosterone ▪ Anti-mullerian hormone (AMH) Testes Men; found in the scrotum ▪ Estradiol ▪ Inhibin B HORMONES ▪ Hormones are released by the endocrine system to coordinate the body’s activities and to keep it functioning properly. ▪ Functions: 1. Regulating growth, development, behavior, and reproduction 2. Coordinating the production, use, and storage of energy 3. Maintaining internal homeostasis such as nutrition, excretion, water and salt balance 4. Reacting to stimuli from outside the body HORMONES ▪ Some hormones are not secreted until an individual reaches a certain age such as the estrogen and testosterone. ▪ There is a difference between short-term and long-term hormones (e.g.: adrenaline and thyroxine). ▪ The production of hormones must be the right amount. ▪ Hormones only work on their target organs. ▪ Hormones are destroyed in the liver after they have performed their function. HORMONE ▪ The body produces more than 40 types of hormones. REGULATION ▪ Feedback mechanisms detect and adjust the amount of hormones circulating in the blood or the amount of other chemicals produced by an initial action. ✓Positive feedback - occurs when a product feeds back to increase its own production. This causes conditions to become increasingly extreme. ✓Negative Feedback - occurs when a product feeds back to decrease its own production. This type of feedback brings things back to normal whenever they start to become too extreme.