2.1 Vertebrate Reproductive Strategies Flashcards
What is Reproduction?
It is the production of a new generation of organisms from an existing generation.
What is the ultimate goal of each species?
It is to produce the maximum number of surviving offspring while using the least amount of energy
What is reproductive effort?
It is to produce the maximum number of surviving offspring while using the least amount of energy
What is asexual reproduction?
It is a mode of reproduction in which a new offspring if produced by a single parent
What types of animals reproduce asexually?
Microscopic animals reproduce asexually
Name 2 benefits of asexual reproduction
- It requires little energy
2. Involves only one parent
Does sexual or asexual reproduction require most energy?
Sexual
Name 9 reproductive strategies
- External fertilisation
- Internal fertilisation
- Ovipary
- Ovovivipary
- Vivipary
- Amniotic egg
- Precocial Development
- Altricial Development
- Parental Care
What is a strategy in terms of living animals?
It is their genetically determined behaviour
Why are reproductive strategies developed?
- In order to enable species to breed successfully
- to ensure that offspring survives till reproductive age
What is fertilisation?
It is the joining of the nucleons of an egg and a sperm
Sperm are —- as they are able to swim
But eggs do not —-
Motile
Move
Where does internal fertilisation take place?
In the water
What type of fertilisation do aquatic animals use?
External fertilisation
Why is external fertilisation not ideal? (2)
- It is wasteful - lots of eggs are produce from which most are eaten
- Fertilisation is not certain
How does external fertilisation maximise reproduction? (2)
- huge number of eggs and sperm are released
- courtship rituals ensure that male and female gametes are close to each other
Why is a huge number of eggs and sperm are released in external fertilisation?
- it increases the probability of fertilisation
- it ensures that enough eggs will be fertilised and grow into adults
Where is most of the reproductive energy spent in external fertilisation?
- almost all of the energy is spent in the production of the eggs
What type of fertilisation do terrestrial vertebrates use?
Internal fertilisation
Describe the process of internal fertilisation. (2)
- male gamers are released directly into body of the female
- eggs are fertilised inside her body
How do birds and reptiles mate?
- males and females line up their cloacae
Males
