reproduction (part 1) Flashcards
Asexual reproduction is…
Asexual reproduction is the process resulting in the production of genetically identical offspring from one parent. It proceeds without the fusion of egg and sperm.
What are the types of asexual reproduction?
- Budding (outgrowth and eventual splitting off of a new individual from the parent.
- Fission (parent separates into two or more offspring about equal size)
- Fragmentation (breaking of parent body into several pieces) and regeneration (regrowth of lost body parts)
Sexual reproduction is…
Sexual reproduction is the creation of offspring through the process of fertilisation. It is the fusion of two haploid sex cells (gametes: egg and sperm) to form a diploid zygote (fertilised egg).
Asexual reproduction produces genetically ____ offspring while sexual reproduction produces genetically ____ offspring.
Asexual reproduction produces genetically identical offspring while sexual reproduction produces genetically dissimilar offspring.
What are the advantages and disadvantages of asexual reproduction?
- Eliminates the need to find a mate
- Permits organisms to multiply quickly without spending time or energy producing sperm and eggs
- HOWEVER, it produces genetically identical offspring, which limits a population’s chances of surviving periods of drastic environmental change.
For animals that are able to reproduce both sexually and asexually, when is each method of reproduction used?
They reproduce by asexual means when environmental conditions are favourable for faster reproduction of offspring. Sexual reproduction happens when conditions are not favourable, so as to increase genetic variation for better adaptation to drastic environment changes.
What is the function of the penis?
The penis contains erectile tissue that can fill with blood and cause an erection during sexual arousal. Its main function is to deliver sperms to the vagina.
What is the function of the testes?
The testes are responsible for making testosterone, the primary male sex hormone, and for producing sperm.
What is the function of the scrotum?
It is a loose, pouch-like sac of skin that hangs behind the penis. It is where the testes are located.
Why are the testes located outside of the body in the scrotum?
Sperm do not develop best at body temperature. The scrotum keeps the sperm forming cells about 2degc cooler, which allows them to function normally. Special muscles in the wall of the scrotum allow it to contract and relax, moving the testicles closer (warmth + protection) or farther away (cool temperature down).
What is the function of the sperm duct?
It delivers sperm from the epididymis to the urethra during ejaculation. Ejaculation is caused by the contraction of muscles in the sperm duct.
The process of producing male gametes (sperm) is called _____.
The process of producing male gametes (sperm) is called spermatogenesis.
The shape of a human sperm is _____, which helps it swim through fluids in the vagina, uterus and oviduct.
The shape of a human sperm is streamlined, which helps it swim through fluids in the vagina, uterus and oviduct.
What is the function of the prostate gland?
It produces a fluid that nourishes the sperm and provides protection from the natural acidity of the vagina.
What is the function of the urethra?
The urethra conveys, at DIFFERENT TIMES, both sperm and urine out of the body, through the penis. (e.g. when penis is erect during sex, flow of urine blocked from urethra, allowing only semen to be ejaculated)
