Unit 13: Reproduction Ch. 23, 24, 25 Why do organisms reproduce? –to pass on genetic code & continue the species 200

What are the 2 Main Types of Reproduction? asexual –H–How many parents? 1 –I–In general, what happens to genetic material during asexual reproduction? genetic material is copied & cell(s) divide(s) –H–How do offspring compare genetically to each other & parent? identical

sexual –How many parents? 2 –In general, what happens to genetic material during sexual reproduction? genetic material combined when gametes (formed by meiosis) fuse during fertilization –How do offspring compare genetically to each other & parent? different –How does sexual reproduction speed up evolution? –increases genetic variety b/c mixing genes

The flower is the plant’s reproductive organ. Sexual Reproduction in Flowering Plants (pistil)

The flower is a plant’s reproductive organ. (pistil)

What are the female parts of a flower? –carpel (pistil) stigma –sticky tip to trap pollen style –long & narrow »sperm travels through ovary –swollen base that contains the ovules »ovules produce eggs Sexual Reproduction in Flowering Plants

What are the male parts of a flower? –stamen anther –produces pollen »contains sperm filament –“stalk” that supports anther Sexual Reproduction in Flowering Plants

What parts of the flower are neither female nor male? –sepals protect young flower bud –leaf-like structures at flower’s base »usually green (can be same color as petals) –petals attract pollinators –located in/above the sepals »can be large & colorful »can be scented »can produce nectar Sexual Reproduction in Flowering Plants

Let’s see if you got that… Sexual Reproduction in Flowering Plants What are 3 & 4 together called? What are 5, 6, & 7 together called? 8

Most flowers have both male & female parts. –What type(s) of pollination can they undergo? self- or cross-pollination Some flowers are only male or female. –What type(s) of pollination can they undergo? cross-pollination –Why is this beneficial? increases genetic variety Sexual Reproduction in Flowering Plants What is pollination? –transfer of pollen from anther to stigma

What happens after fertilization in flowering plants? –ovule matures into seed seed contains embryo & food –ripened ovary becomes the fruitripened ovary becomes the fruit Seed coat embryo Sexual Reproduction in Flowering Plants

Sexual reproduction in humans… Sexual Reproduction in Animals

*Accessory glands seminal vesicle, prostate, bulbourethral (Cowper’s) gland penis Male Reproductive System Anatomy—Side View

Male Reproductive System Parts & Their Functions 1. Testes (testicles) (singular = testis)—glands that produce sperm in seminiferous tubules; produce testosterone (hormone) ‒ ***scrotum—pouch of skin containing the testes; protects & acts as a climate control system for the testes 2. Epididymis–tube that rests on each testicle, connecting it to vas deferens. Sperm are stored and mature here before entering vas deferens. 3. Vas deferens—tube that carries sperm from epididymis to urethra in preparation for ejaculation 4. Accessory glands (prostate, seminal vesicle, bulbourethral/Cowper’s gland) — add seminal fluids to sperm (along vas deferens) to form semen –fluids = water, nutrients/sugar (provide sperm w/ energy), & buffers (neutralize pH in urethra & vagina 5. Urethra—carries urine from bladder (during urination) & semen from reproductive system (during ejaculation) to outside of body through penis 6. Penis—used to insert sperm into vagina of female

1. Sperm cells are produced by the testes in the seminiferous tubules. 2. Sperm are stored in the epididymis (& mature). 3. Sperm pass through the vas deferens. 4. Accessory glands along the vas deferens add seminal fluids (water, buffers, & nutrients) to sperm. –combo of sperm & fluid together is called semen 5. Semen passes through the urethra –& out of the penis during ejaculation Male Reproductive System Anatomy: What Path Does Sperm Follow from Production to Ejaculation? ***Sperm do NOT pass through accessory glands!!!

Let’s Review G A B C D E F

Male Reproductive System Anatomy— Front View

Let’s Review A B C F E D G

Structure of Male Sperm

Female Reproductive System Anatomy— Side View (fallopian tube)

1. Vagina (birth canal)—tube that joins cervix to outside of body; sperm inserted by penis here, baby exits body here 2. Cervix—opening in lower part of uterus; allows sperm to enter & menstrual blood to exit 3. Uterus (womb)— fertilized egg implants in lining & embryo/fetus develops here 4. Oviducts (Fallopian tubes)—tubes attached to upper part of uterus; serve as tunnels for ova (egg cells) to travel from ovaries to uterus; conception/ fertilization of egg by sperm normally occurs here ***Ovaries—small, oval-shaped glands located on either side of uterus that produce eggs and hormones (progesterone & estrogen); NOT actually attached to oviduct Female Reproductive System Parts & Their Functions

What path does sperm follow until fertilization occurs? 1.sperm enters vagina 2.passes through cervix 3.enters uterus 4.travels into oviduct (fallopian tube) where fertilization normally occurs What happens after egg is fertilized in the oviduct (f.t.)? 1.fertilized egg (zygote) travels to uterus 2.implants in lining of uterine wall (endometrium) Where does the development of the embryo/fetus occur? 1.normally occurs in uterus Female Reproductive System Anatomy: What Path Does Sperm Follow Until Fertilization Occurs? Where Does Fertilization Occur? Where Does the Development of the Embryo/Fetus Occur?

Let’s Review Female Reproductive System Anatomy—Side View A B C D (oval object in back) E

(fallopian tube) Female Reproductive System Anatomy—Front View

Where does: fertilization take place? implantation take place? the fetus develop? Female Reproductive System Anatomy— Front View What is the pathway that sperm follows prior to fertilization? A B C D E

Formation of Eggs Where do eggs form? –In follicles in the ovaries. What is ovulation? –the release of an egg from follicle

What controls the menstrual cycle? –hormones What is the role of the menstrual cycle? –prepares uterus for possible pregnancy How often does the menstrual cycle occur? –usually monthly (~28 days) What are the 4 phases of the menstrual cycle? 1.thickening of uterine lining 2.ovulation egg matures & is released 3.passage of egg into uterus (if not fertilized) ~day 14 4.loss of unfertilized egg & lining (menstruation) Human Menstrual Cycle

Fertilization The Miracle Begins What is the pathway that sperm follows prior to fertilization?

Fertilization & Development

(below) Embryo & Fetal Development Animation Developmental Timeline

Labor & Delivery The big day! –3 stages 1.dilation of cervix 2.delivery of newborn –contractions of uterus push baby out head first 3.delivery of placenta –also by contractions of uterus