Chapter 46: Reproduction

Key Term

• sexual reproduction

• the reproduction involving the union or fusion of a male and a female gamete

• egg

• animal reproductive body consisting of an ovum or embryo together with nutritive and protective envelopes

• sperm

• male reproductive cell

• asexual reproduction

• reproduction without the fusion of gametes

• budding

• reproduction of some unicellular organisms by growth and specialization followed by the separation by constriction of a part

of the parent

• Ovulation

• expulsion of an ovum from the ovary

• hermaphroditism

• showing characteristic of both sex

• fertilization

• process in sexual reproduction in which male and female reproductive cells join to form a new cell

• External fertilization

• process in which eggs are fertilized inside the female body

• Internal fertilization

• process by which the female lays eggs and the male fertilizes them once they are outside the female

• gonads

• reproductive gland-male, testes; female-ovaries

• spermathecae

• sacs in which sperm may be stored for expanded periods

• cloaca

• Ovulation

• expulsion of an ovum from the ovary

• hermaphroditism

• showing characteristic of both sex

• fertilization

• process in sexual reproduction in which male and female reproductive cells join to form a new cell

• External fertilization

• process in which eggs are fertilized inside the female body

• Internal fertilization

• process by which the female lays eggs and the male fertilizes them once they are outside the female

• gonads

• reproductive gland-male, testes; female-ovaries

• spermathecae

• sacs in which sperm may be stored for expanded periods

• cloaca

• common opening for the digestive, excretory, and reproductive systems in non-mammilian vertebrates

• follicles

• clusters of cells surrounding a single egg

• hymen

• thin piece of tissue partially covering the vaginal opening

• clitoris

• organ in the female that engorges with blood and becomes erect during sexual arousal

• prepuce

• fold of skin covering the head of the clitoris and penics

• mammary glands

• Exocrine glands that secrete milk to nourish the young. theses glands are characteristic of mammals

• seminiferons tubules

• highly coiled tubes in the testes in which sperm are produced

• leydig cells

• located between the seminiferous tubules of the testes, these cells produce testosterone and other androgens

• scrotum

• pouch of skin outside the abdomen that houses a testis; functions in cooling sperm, thereby keeping them viable

• epididymis

• coiled tubule located adjacent to the testes where sperm are stored

• ejaculation

• propelling of sperm from each epidermis through the an deferens

• vas deferens

• tube is the male reproductive system in which sperm travel from the spididymis to the urethra

• ejaculators duct

• short section of the ejaculatory route in mammals formed by the convergence of the cas deferens and a duct from the seminal vesicle.

• transports sperm from the vas deferens to the urethra

• semen

• fluid that is ejaculated by the male during organs; contains sperm and secretions from several gland of the male reproductive tract

• seminal vesicles

• gland in males that secretes a fluid component of semen that lubricates and nourishes sperm

• prostate gland

• gland in human males that secretes an acid neutralizing component of semen

• Penis

• copulatory structure of male mammals

• gametpgemesis

• production of gametes

• spermatogenesis

• formation and development of sperm

• menstrual cycle

• type of reproductive cycle in higher female primates, in which the non-pregnant endometrium is

shed as a bloody discharge through the cervix into the vagina

• Oogenesis

• process in the ovary that results in the production of female gametes.

• ovarian cycle

• cyclic recurrence of the follicular phase, ovulation, and the luteal phase in the mammalian ovary, regulated by hormones

• follicular phase

• portion of the ovarian cycle during which several follicles in the ovary begin to grow

• luteal phase

• portion of the ovarian cycle during which endocrine cells of the corpus luteum secrete female hormones

• proliferative phase

• portion of the menstrual cycle when the endometrium regenerates and thickens

• secretory phase

• portion og the menstrual cycle when the endometrium continues to thickens, becomes more vascularized, and develops glands that secrete a fluid rich in glycogen

• menstrual flow phase

• portion of the menstrual cycle when menstrual bleeding occurs

• vasocongestion

• filling of a tissue with blood caused by increased blood flow through the arteries of that tissue

• Orgasm

• characterized by thythmic, involuntary contractions of the reproductive structure in both sex

• conception

• fertilization of a penis into a vagina, also called sexual intercourse

• human chorionic gonadotropin (hCG)

• thin membrane that partly covers the vaginal opening in the human female’ raptured by sexual intercourse or other vigorous activity

• Pregnancy( gestation)

• condition of carrying one or more embryos in the uterus

• trimester

• human development. one of three 3- month long period of pregnancy

• placenta

• structure in the pregnant uterus for nourishing a viviparous fetus with the mother’s blood supply; formed from the uterine lining and embryonic

membranes

• fetus

• developing human from the ninth week of gestation until birth; has all the major structures of an atult

• labor

• series of strong, rhythmic contractions of the uterus and vagina during child birth

• lactation

• continued production of milk

• contraception

• prevention of pregnancy

• rhythm method

• refraining from intercourse when conceptions is most likely in the few days before and after ovulstion

• natural family planning

• form of contraception that relies upon refraining from sexual intercourse when conception is most likely to occur; also called the rhythm method

• Tubal ligation

• sterilization in which a woman’s two oviducts are tied closed to prevent eggs from reaching the uterus; a segment if each oviduct is removed

• Vasectomy

• cutting of each vas deferens to prevent sperm from entering the urethra

• assisted reproductive technologies

• methods used to achieve pregnancy by artificial or partially artificial means. It is reproductive technology used primarily for infertility treatments, and is also known as fertility treatment.

• in vitro fertilization (IVF)

• fertilixation of ova in laboratory containers followed by artificial implantation of the early embryo in the mother’s uterus

• intrpcyoplasmic sperm injection (ICSI)

• test-tube fertilization procedure in which a sperm is injected directly into an egg to achieve fertilization. ICSI is done for male infertility

Sexual and Asexual Reproduction

• Sexual Reproduction• Animal reproductive takes many forms

• Aspects of animal form and function can be viewed broadly used as adapations contributing to reproductive success

• Sexual reproduction is the creation of an offspring by fussion of a male gamete and female gamete to form a zygote

• Asexual Reproduction• Needs one individual

• Is creation of offspring without the fusion of the egg and sperm

Budding

• New individual arise from outgrowths of existing one

External and internal fertilization

• External Fertilization• Eggs shed by the female are fertilized by sperm in the external

environment

• Internal Fertilization• Sperm are deposited in or near the female reproductive tract and

fertilization occurs within the tract takes place within the female reproductive system. Provides protection and parental care.

Trimesters

• First trimester• Is the time of most radical changes for both mother and the embryo

• All major organs are form

• All the major structure are present by week 8 and the embryo is now call a fetus

• Second trimester• Fetus grows and is very active

• Mother may feel the fetus

• Uterus grows enough for the pregnancy to become obvious

• Third trimester• The fetus grows and fills the space within the embryonic membranes

• Complex interplay of local regulation and hormones induces, and regulates labor, the process in which birth occurs

Contraception

• Delibrate prevention of pregnancy can be achieved in a number of ways

• Contraception methods falls into 3 categories• Preventing the release of egg and sperm

• Keep egg and sperm apart

• Preventing the implantation of the embryo