Paper 1 - Reproduction Flashcards
In plants, how is the ovary adapted for pollination?
Contains ovules to be fertilised
In plants, how is the style adapted for pollination?
- Long and strong to hold up the stigma
- Pollen tube grows down style and into the ovary
In plants, how are the anthers adapted for pollination?
- Produces pollen
- Insects can brush against it to pick up pollen
- Wind can blow it away to carry pollen to other plants
Describe the structure of a wind-pollinated flower
- Feathered stigma
- Less exposed anthers
- Style
- Filament
- Small and not colourful petal
- No nectaries
- Overy
- Sepal
Describe the structure of an insect-pollinated flower
- Stigma
- Exposed anthers
- Style
- Filament
- Colourful and large petal
- Nectaries
- Overy
- Sepal
How is the sepal adapted for pollination?
- Forms helmet shape
- To protect the developing flower
How is the stigma adapted for pollination?
It is sticky to allow pollen to stick to it securely
How many daughter cells does meiosis create?
4
What are the daughter cells of meiosis called?
Haploids
What happens to the ovules when the pollen tube grows and the ovule is fertilised?
Turns into fruit
What is the role of oestrogen in the menstrual cycle?
Builds up uterus lining
What is the name given to the short sprout from a seedling that grows up/down shorter after germination?
Grows up : Plumule
Grows down : Radicle
How is the male reproductive system adapted for its function?
- Seminal gland produces seminal fluid to keep sperm cells alive when travelling to the egg
- Penis’ external location allows for ejaculation into the vagina
- Urethra is elastic and stretchy so can allow for differing volumes of semen or urine to pass through
- Testicles are highly sensitive to protect them so they can produce sperm
- Foreskin insulates and protects the penis to keep sperm warm and alive
- Scrotum insulates and protects the testicles to keep them warm so that they can produce sperm
What is the role of progesterone in the menstrual cycle?
Maintains uterus lining
What are the roles of oestrogen in the development of secondary sexual characteristics?
- Widen hips for child birth
- Breast development
- Pubic hair growth
- Periods begin
How do germinating seeds utilise food reserves until the seedling can photosynthesize?
- Water is used to activate enzymes to break starch down into Glucose
- O2 is used for respiration to produce ATP energy
- Warmth allows enzymes to work faster
What is the role of the placenta in the nutrition and development of the embryo?
- Villi provide a large surface area for fast diffusion of nutrients
- Capillaries remove waste products
- Capillaries carry blood to and from the placenta to maintain a concentration gradient
- Short distance between mother’s and embryo’s blood for fast diffusion of nutrients
How can plants reproduce?
- Asexually by natural methods (like runners)
- Asexually by artificial methods (like cuttings)
- Sexually by insect or wind pollination
What are the differences between sexual and asexual reproduction?
- There is no genetic variation in asexual reproduction but there is in sexual reproduction
- Asexual reproduction does not require a mate but sexual reproduction does
- 100% of advantageous alleles are passed on in asexual reproduction but there is no guarantee of this in sexual reproduction
- Asexual reproduction is favoured by most plants but sexual reproduction is favoured by most animals
- Sexual reproduction requires male and female gametes but asexual reproduction does not
How is the developing embryo protected by amniotic fluid?
- Acts as a shock absorber
- Protects embryo from bumps
How many daughter cells does mitosis create?
2
What are the daughter cells of mitosis called?
Diploids
How is the petal adapted for insect-pollination?
- Large surface area as a ‘landing pad’ for insects
- Colourful to attract insects
