Download presentation
Presentation is loading. Please wait.
Published byBruce Dawson Modified over 9 years ago
1
Reproduction & Development (PB Lecture18 – Spring 2008 Althoff, reference Ch. 36) Animal Reproduction Human Reproduction Animal Development
2
Modes of Reproduction ______________ budding (in Hypha ) parthenogenesis (in some insects, lizards, salamanders) spontaneous fission (planaria) _____________ “true” hermaphoditism (rare, few insects) _____________ fertilization—union of gametes from two different individuals
3
HYDRA LIFE CYCLE
4
BUDDING…. by Hydra ( who also carrying on sexual reproduction )
5
Asexual Reproduction ____________________--females (of some species) reproduce without fertilization…resulting in haploid offspring. Some species can do this AND sexual reproduction example: Aphids can do both: no wasted energy or gametes in midst of plenty
6
Aphid “taps” into phloem tissue of plants (the “sugar” pipeline)….so, rich source of energy and other nutrients allows for optimum production of young…without having to find a mate !!!!
7
Some species… it is a ________ world only, thus, considered _________species FISH: mollies and platies LIZARDS: whiptails
8
Planaria Spontaneous (binary) fission
9
Sexual Reproduction: the norm among Animalia species Some species have “both sets” of sex organs (hermaphroditic: earthworms example) Just one set of sex organs ( or ) is the norm Two basic categories: ______________ fertilization—most primitive ______________ fertilization—most advanced
10
Human Reproduction Reproductive system consists of 2 components: (1) _______: testes or ovaries which produce gametes and sex hormones (2) ________________: a) males: conduct (move) gametes b) females: house embryo/fetus
11
TESTIS PENIS Bladder Urethra EPIDIDYMIS VAS DEFERENS SEMINAL VESICLE PROSTATE GLAND testes epididymis vas deferens bulbourethral gland prostrate gland seminal vesicle urethra penis B.G.
12
Semen Combination of _________ + secretions from 3 glands: 1) seminal vesicles: thick, viscous fluid containing _________ for possible use by sperm 2) prostrate gland: milky, ________ fluid that a) activates/increases sperm motility b) protects sperm in vagina’s low pH (3.8 to 4.5) environment 3) bulbourethral glands: muscous secretions with a ____________ effect (some pre- ejaculate fluid)
13
EPIDIDYMUS TESTIS SEMINIFEROUS TUBULES Site of gamete production (_________ occurs here) TESTES: site of gamete production, “__________” environment
14
SPERMP ____________ (a lysosome) MITOCHONDRIA
15
OVIDUCT OVARY UTERUS CERVIX VAGINA
16
OVARIAN CYCLE 28-days in humans here occurs at this stage
17
OVARY site of oogenesis does NOT take place in the ovary!
18
1 2 3 4 5 67 Developing, ovulating, …and gone! The ovary
19
Follicle Ovulation Evidence of Ovulation New __________ containing primary oocyte Developing follicle Mature follicle with secondary oocyte ______________ – egg erupts from ovary into oviduct…”ruptured follicle remains Egg goes into oviduct, “that” follicle is done for life. But, if pregnancy occurs it will become a _________________ (easily detected) producing primarily ______________ & 7 No pregnancy, then “that” corpora luteum reduces in size and quits producing progesterone
21
Menstrual Cycle - Under hormonal control GnRH - gonadotropin-releasing hormone FSH - follicle stimulating hormone LH - lutenizing hormone ESTROGEN PROGESTERONE WHERE DO THESE HORMONES COME FROM?
22
________ (HT) _______ (AP) ______ (AP) ___________(OV) _______________ (OV) HT =hypothalamus AP = anterior pituitary OV = ovary (oocyte follicle corpus luteum
23
DAY OF MENSTRUAL CYCLE HORMONE CONCENTRATION 01428
24
HORMONE CONCENTRATION DAY OF MENSTRUAL CYCLE 01428
25
DAY OF MENSTRUAL CYCLE 01428 THICKNESS Uterine lining menstruation
26
Post - ovulation 1) SECONDARY OOCYTE (EGG) enters OVIDUCT with action by fimbriae 2) sperm “meets” egg somewhere in oviduct resulting in _______________ 3) ___________ results, and travels on 4) ______________ develops and implants in the _________________ 5) _____________ develops into ________
31
= when 3 germs layers have formed. Occurs 3 rd week of development
32
Embryonic layerAdult tissue Ectoderm Mesoderm Endoderm GERM LAYERS specific tissues/organs
33
Human embryo at beginning of week 5 SOMITES
34
The PLACENTA – the most ______________ “support” structure for development
35
PLACENTA Maternal blood and fetal blood never mix… because exchange occurs across the ___________________ Chorionic villi: ______________ fetal side ______________ maternal side Risk: harmful chemicals moving across placenta to fetal side… _______________ during EMBRYONIC (0-90 days) stage because various structure first forming OTHER TIMES (including 3-9 months) different organs “at risk” because they develop at different times during pregnancy
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.