Topic 3: Reproduction And Inheritance Flashcards
What is fertilisation?
- The fusion of male gametes to form diploid (46 chromosomes) zygotes
- It then undergoes mitosis to develop into an embryo
What are the outer parts of a flower
- Sepals
- Petals
What is the male reproduction called and what do they consist of?
Stamens:
- Anthers
- Filaments
What is the female reproduction of a flower called and what do they consist of?
Pistils:
- Stigma
- Style
- Pollen tube
- Ovary
What are some insect pollinated flowers adaptations?
- Large petals & brightly coloured
- Nectar scents attracts insects
- Moderate amount of pollen grains
- Pollens grains are sticky and spiky
- Pollens from anthers are firmly attached to which is easy to brush against insects
- Stigma is sticky so it can catch pollen grains
What are some adaptations wind pollinated flowers have?
- They have a large amount of pollen grains as population can be increased quickly
What are the conditions needed for seed germination
- Water
- Oxygen
- Warmth
How can you investigate for germination
- Have four test tubes
- One with all conditions present
- The rest with different conditions
Explain the process of pollination and seed & fruit formation
- Pollen grains are transferred from the Anther to the Stigma
- When the stigma has pollen grains, the pollen tube grows down the style until it reaches the ovary
- The nucleus of the pollen grains then goes down to the Ovule for fertilisation
- The ovule will form a seed and develop into a fruit
What are the two methods for plant’s asexual reproduction
- Runner (natural)
- Cutting (artificial)
Describe the structure of the male reproductive system
- Bladder
- Sex Gland
- Sperm duct
- Urethra
- Testis
- Penis
Describe the structure of a female reproductive system
- Bladder
- Oviduct
- Ovary
- Uterus
- Cervix
- Urethra
- Vagina
Where is oestrogen produced and what do they do?
- They are produced in the ovaries
- They stop secretion of FSH and stimulates the Pituitary Gland to secrete LH
Where is progesterone produced and what does it do?
- It is produced in the ovaries
- It maintains the uterus lining for pregnancy by thickening blood vessels
Where is FSH produced and what does it do?
- It is produced in the pituitary gland
- It causes egg cell to be mature and develop.
- Stops ovaries from secreting oestrogen
Where is LH produced and what does it do?
- It is produced in the pituitary gland
- It stimulates ovulation and stimulates ovaries to release progesterone
What is a placenta ?
- It is the connection between inner Uterine wall and Foetal membrane via Umbilical Cord that facilitates the exchange of materials between Mother and developing Fetus
What is an amniotic fluid and what role does it play?
- It is a fluid that protects the baby from shocks or hits
- It ensures the baby doesn’t have to support its own weight
- It is the fluid when there is a “water break”
What sex hormones do female have and what are the effects to their body?
- Oestrogen
Effects: - Growth of body hair
- Development of breast
- Menstrual cycle begin
