Chapter 11: Reproduction and Developmental Biology

types of asexual reproduction

binary fission, budding, fragmentation, parthenogenesis

which organisms reproduces with binary fission

prokaryotes, eukaryotic organelles

binary fission

replicated circular DNA migrate to opposite ends of a cell/organelle, septum forms in middle to divide into 2 genetically identical products

budding

parent organism develops a mitotic bud that becomes a new organism which can detach or remain attached

which organisms reproduces with budding

some fungi and animals (yeast, hydra)

fragmentation

organism splits into fragments, each fragment regenerates into a compkete organism

which organisms reproduces with fragmentation

flatworm, starfish

parthenogeneis

unfertilized egg develops into a viable embryohydra

which organisms reproduces with parthenogeneis

honeybees

how does sexual reproduction work starting with germ cells

differentiate into gametocytes, then produce gametes by meiosis

spermtogenesis

formation of mature haploid gametes from diploid germ cells through a series of steps

what are haploid gametes called in spermatogenesis

spermatozoa

what are diploid germ cells called in spermatogenesis

spermatogonia

how are spermatids form

spermatogonia differentiate into spermatocytes, then undergo 2 meiotic divisions

what many spermatids are formed

4

what happens during the final stage of spermatogenesis

haploid spermatids mature into motile spermatozoa

what is the sperm pathway

seminiferous tubules, epididymis, vas deferens, ejaculatory duct, urethra, exits the penis

what is the site of spermatogenesis

seminiferous tubules

what kind of cells do seminiferous tubules contain

sertoli cells

sertoli cells

activated by follicle stimulating hormone, surround and nourish sperm

how, where, and why is immature sperm transported

by peristalsis to epididymis for storage and maturation

what is the epididymis

duct around the testes

where do the sperm move through

vas deferens into the ejaculatory duct propelling sperm into urethra leading to ejaculation out of penis as semen

mnemonic for sperm pathway

SEVEn UP

the structure of the sperm

head, midpiece, tail

the head of the sperm

contains nucleus and acrosome

the midpiece of the sperm

mitochondria

the tail of the sperm

long flagellum to propel sperm

hormones in males

follicle stimulating hormone, luteinizing hormone, testorestone

follicle stimulating hormone (FSH)

stimulates sertoli cells for spermatogenesis in seminiferous tubules

luteinizing hormone (LH)

stimulates leydig cells to produce testosterone

testosterone

responsible for male secondary sex characteristics, supports spermatogenesis