Reproduction Flashcards
What is the role of meiosis?
used to produce gametes
What is the role of mitosis?
growth and repair
What kind of cells does meiosis produce?
genetically varied
What kind of cells does mitosis produce?
genetically identical
How many cells does meiosis produce?
four
How many cells does mitosis produce?
two
How many cell divisions take place in meiosis?
two
How many cell divisions take place in mitosis?
one
Does meiosis produce haploid or diploid cells?
haploid
Does mitosis produce haploid or diploid cells?
diploid
Is meiosis used for sexual or asexual reproduction?
sexual (makes gametes)
Is mitosis used for sexual or asexual reproduction?
asexual (cloning)
Describe the process of mitosis
DNA is replicated
nuclear membrane breaks down
chromosomes line up
chromatids pulled apart to opposite poles
two cells are formed
Describe the process of meiosis
DNA is replicated
homologous pairs of chromosomes join
exchange of DNA
pulled apart to opposite poles
mitosis takes place
four cells are formed
How many chromosomes does a human body cell contain?
46
23 homologous pairs
Why are gametes haploid cells?
half originate from male
half originate from female
Define fertilisation
fusion of male and female haploid gametes to produce a zygote with diploid chromosomes
What is the first cell produced by fertilisation called?
zygote
Why do sperm cells and egg cells only have 23 chromosomes?
half of genetic information from each parent to form diploid cell
How many chromosomes does a human diploid cell have?
46
How many chromosomes does a human haploid cell have?
23
What is external fertilisation? Give an example
takes place outside body, Fish
What is internal fertilisation? Give an example
takes place inside female body,sexual intercourse
What is the function of the egg cell?
be fertilised and form a zygote
What is the function of the sperm cell?
to fertilise the egg cell and form a zygote
How is the egg cell adapted for its function?
nutrients ; for zygote
membrane ; only allows one sperm to fertilise it
large ; space
How is the sperm cell adapted for its function?
mitochondria ; energy
streamlined ; swimming
flagellum ; swimming
enzymes ; break through egg
What is the ovary?
where egg cells are formed by meiosis
produces oestrogen and progesterone
What is the oviduct?
egg cells travel down this to the uterus
site of fertilisation
How is the oviduct adapted for its function?
lined with cilia to move the cell
What is the uterus?
where embryo will develop when fertilised zygote implants in uterus
How is the uterus adapted for its function?
thick muscular wall ; contracts during labour
What is the cervix?
narrow opening to uterus
How is the cervix adapted for its function?
dilates during labour for baby to be born
What is the vagina?
muscular tube that leads from cervix to inside woman’s body
What is the function of the testes?
where sperm cells are formed by meiosis
produces testosterone
What is the sperm duct?
maturing sperm transported along this tube
What is the function of the seminal vesicle and prostrate gland?
releases liquids into sperm duct to form semen
provides nutrients to sperm