D3.1 Reproduction Flashcards
sexual vs asexual reproduction
- gametes fertilized vs organism replication
- 2 vs 1 parent
- genetically unique vs identical offspring
types of asexual reproduction
binary fission, mitosis, budding, fragmentation, vegetative reproduction (new plants from roots, etc.), parthenogenesis (developing egg without sperm)
draw and label the female reproductive system
vagina, cervix, uterus, oviduct/Fallopian tubes, ovaries (front and side view)
gonad
organ producing gametes (ovary and testis)
function of ovaries
produce oestradiol and eggs as secondary oocytes, ovulation in corpus luteum temporarily produces progesterone
function of Fallopian tube
carry egg from ovary to uterus
function of uterus
embryo implantation and development
function of endometrium
vascular inner lining of uterus
draw and label the male reproductive system
testis, scrotum, epididymis, vas deferens, urethra, seminal vesicle, bladder, prostate gland, Cowper’s gland, penis/erectile tissue, anus (side view)
function of testes
produces sperm in seminiferous tubules
function of epididymis
where sperm are stored and mature
function of scrotum
protects testes and sperm grow at cooler temperature
function of vas deferens
carries sperm to urethra
function of seminal vesicle
produces seminal fluid
function of prostate gland
produces most of the semen, used to neutralize vaginal fluid
function of Cowper’s gland
produces lubricating mucus
menstrual cycle
- hypothalamus produces gonadotropin-releasing hormone (GnRH)
- GnRH stimulates pituitary gland to produce follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
- FSH and LH stimulate ovaries to produce oestradiol
- Oestradiol stimulates endometrium to increase vessels and pituitary gland to increase production of FSH and LH (positive feedback)
- Increase in FSH and LH stimulates arrangement of follicle cells in two rings around oocytes, producing Graafian follicles
- Single follicle enters Fallopian tube after ovulation, outer ring stays in ovaries
- Outer follicles form corpus luteum, producing progesterone to maintain endometrium and dividing to heal would from ovulation
- Corpus luteum produces progesterone for 10-12 days, signalling to hypothalamus no GnRH (negative feedback)
- When corpus luteum diminishes, no more endometrium vessels, low levels oestradiol and progesterone result in menstruation and new cycle
function of luteinizing hormone
stimulates follicles to mature and release eggs
2 components of menstrual cycle
ovarian and uterine cycle
process of fertilization
- sperms release enzymes from acrosome penetrates follicle layer, then zona pellucida (glycoprotein gel), then plasma membrane
- egg releases vesicles to destroy sperm flagellum and mitochondria, leaving male nucleus with female in egg (pronuclei)
- pronuclei replicate DNA then fuse, prepare for mitosis (chromosomes and spindles form, nuclear membrane dissolves)
- first mitosis 30 h later, 16 cells after 3 days
reasons for infertility
low sperm count, impotence, abnormal ovulation, blocked Fallopian tubes
process of in vitro fertilization
- woman takes drugs to stop hormones of menstrual cycle
- woman injected with FSH to produce more Graafian follicles (superovulation), and hCG to maintain endometrium
- eggs harvested surgically, sperm from ejaculation
- eggs and sperm mixed in multiple dishes, 1-3 healthy embryos implanted into uterus (unused embryos are frozen)
what plant structures produce gametes?
ovules and pollen grains
how do ovules and pollen grains reproduce, in contrast to plant gametes?
meiosis vs mitosis