3a (Reproduction) Flashcards
Sexual reproduction
- The fussion of a male and female gamete to produce a zygote that undergoes cell division and develops into an embryo
- Genetic variation
Asexual reproduction
- Reproduction with one parent
- No genetic variation
Insect pollinated flower
- Colourful petals (to attract insects)
- Sticky polen (to stick insects bodies)
- Large petals (to attract insects)
- Nectar (to attract insects, they feed)
wind pollinated flower
- Not colourful petals, usually green
- Small, light grain pollen (to be carried by the wind)
- Small petals (needs to be light)
Seed / fruit formation
- Pollen lands on stigma
- Pollen tube is formed and fertilises ovule in ovary
- Seed / fruit is formed
Gamete
Sex cell
Zygote
Fertilised egg
Mitosis
Regular cell division
meiosis
cell division to form gametes
Plants asexual reproduction
Natural –> Runners
Artificial –> Cuttings
Role of oestrogen in menstrual cycle
Responsible fro re-growth of uterus lining
Role of progesterone in menstrual cycle
Keeps the uterus lining in place
Placenta
- Allows the embryo to obtain materials suhc as oxygen and nutrients from the mothers blood
- Allows the emrbyo to get rid of waste products such as carbon dioxide and urea
Amniotic fluid
Amniotic fluid surrounds and protects the embryo from physical damage
uterus
Where the embryo becomes attached through the placenta
Testes
These make sperm cells
Vagina
Where sexual intercouse takes place
Ovaries
Egg are made here
Oviduct
Fertilisation of the egg should occur here occur here
Cervix
The entrance to the womb or uterus
Prostate gland
This organ makes the fluid found in semen
Urethra
A tube rube running through the penis
Puberty boys (testosterone)
- Sperm production starts
- Sexual organs grow and develop
- Growth of hair
- Increase in body mass
- Deeper voice
- broader shoulder
Puberty girls (oestrogen)
- Menstrual cycle begins
- Female sexual organs grow and develop
- Growth of hair
- Body mass increases
- Voice deepens
How germinating seeds utilise food reserves
The absorption of water triggers the synthesis of Amylase
Amylase breaks starch reserves into glucose
Glucose can be used as a source of energy via aerobic respiration
Mitosis (detail)
Cells made are genetically identical and are called diploid
Meiosis (detail)
4 genetically identical gametes are formed (haploid)
