Reproduction Flashcards
What is sexual reproduction?
In sexual reproduction, two parents create non-identical offspring, inheriting characteristics from both parents
What is fertilisation?
Fertilisation is the fusion of a male and female gamete to produce a zygote that undergoes cell division to become an embryo
What is the female reproductive part of a plant?
The carpel (the stigma, style, ovary and ovule)
What is the male reproductive part of a plant?
The stamen (the anther and filament)
What is pollination?
The transfer of pollen from the anther of a plant to the stigma
What are some adaptations of insect-pollinated plants?
- large, brightly colored petals
- sweet scent
- contain a nectary
- sticky coating on stigma so that pollen sticks to it when insects brush past
What are some adaptations of wind-pollinated plants?
- small petals, often brown or dull green
- no scent
- no nectary
- feather or net like stigma to catch pollen, often hangs outside the flower
What is asexual reproduction?
In asexual reproduction, a single parent creates genetically identical offspring
Give examples of insect-pollinated plants
Daisy, orchid, lily
Give examples of wind-pollinated plants
Sugar cane, wheat, grassflower
How can plants encourage cross-pollination?
- having the stigma higher than the stamen
- having the stamen and stigma mature at different times
What happens when a pollen grain lands on a stigma?
- a pollen tube starts to grown through the style
- digestive enzymes a reproduced by the tip of the pollen tube, enabling it to grow through the tissues in the style
- the pollen tube enters the ovary through the micropyle and reaches the ovule
- after fertilisation, the ovule (containing the fertilised egg) develops into a seed
- the ovule wall becomes the seed coat (testa) and parts of the flower surrounding the ovule develop into fruit
What conditions are needed for seed germination?
WOW
Water
Oxygen
Warm temperature
How can seeds be dispersed?
By wind (sycamore) By water (coconut) By animals (berries) Mechanically (lupin)
How does a seed gain energy for growth?
- a developed seed contains an embryo and a food store (cotyledon) wrapped in the testa
- when water enters the seed through the micropyle, it activates the enzymes which break down starch into glucose
- the glucose is used in respiration to provide the plant with energy for growth
- once the plant has grown enough to produce green leaves, it can photosynthesise
Describe a process of natural asexual reproduction in plants
Strawberries:
- the parent plant sends out runners which grow horizontal along the ground
- at certain points, small roots (adventitious roots) grow into the soil
- eventually the runner dies and a new plant is established
Describe a process of articulate asexual reproduction in plants
Cuttings
- a small length of stem is taken from the plant and places into water or soil
- growth hormones/regulators may be added to encourage adventitious roots to grow
What is the testis?
Where sperm are made
What is the prostate gland?
Where semen is produced (the fluid in which sperm swim) and is where the vas deferens and urethra join
What is the pubic bone?
It forms part of the pelvic girdle
What is the vas deferens?
A muscular tube which carries sperm from testis towards the urethra
What is the bladder?
It stores urine produced by the kidneys
What is the urethra?
The tube that carries sperm and urine from the body
What are the male gametes?
Sperm
