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Flashcards in Reproduction in vertebrates Deck (84)
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1

Define reproduction

the process of producing a new generation of organisms from an existing generation

2

How do all vertebrates reproduce?

sexually

3

What does sexual reproduction involve?

The production of gametes in male and female parents

4

What forms when a gamete from each parent fuses?

A zygote

5

In order for two gametes to produce a single organism what needs to happen?

the gametes must be brought into contact with each other
developing embryo must be fed and protected
the young must survive young enough to reach sexual maturity

6

What do different organisms use various strategies to do?

To bring gametes into contact
To feed developing embryo
To protect developing embryo
To ensure the young survive long enough to reach sexual maturity

7

What do vertebrate groups carry out in different ways to ensure that it will be successful?

sexual reproduction

8

What are the different stages of sexual reproduction?

fertilisation
development of zygote
development of young after birth/hatching
level (or absence of) parental care

9

What are the possible names of an unborn baby/egg?

zygote
blastocyst
embryo
foetus

10

Define reproductive strategies

the way in which each animal species ensures that each stage is completed successfully

11

What are different adaptations that different reproductive strategies can come about from?

structural adaptations
functional adaptations
behavioural adaptations

12

What can improve the chances of fertilisation (or survival of the offspring)?

adaptations which ensure that reproductive strategies are completed successfully.

13

What happens during fertilisation?

the nucleus of a sperm cells enters the egg cell and fuses with the nucleus of the ovum

14

Which part of the sperm cell enters the egg cell?

the nucleus of a sperm cell enters the egg cell

15

What does motile mean?

able to actively move
Sperm are motile; ova are non-motile

16

What two things are essential for a sperm cell to successfully fertilise an egg cell?

the sperm must be protected from drying out
the sperm must be guided to the ova

17

Is fertilisation external or internal?

It can be both

18

Where does external fertilisation occur most frequently?

In most animals that breed in water

19

How do animals in water undergo external fertilisation?

Fish and amphibians release eggs and sperm into the water and fertilisation occurs outside the body of the female

20

What are some disadvantages of external fertilisation?

animals are dependent on water
large amounts of sperm and eggs required
many gametes will be eaten by predators
unstable environmental factors (temp, PH, currents)

21

What are some advantages of external fertilisation?

no need for parental care (reduces energy input from parents)
young are widely dispersed by currents (reduces competition)

22

Where do offspring that undergo external fertilisation obtain food from?

They obtain food from the environment.
This reduces energy input from parents to offspring

23

Where does internal fertilisation occur mainly?

in terrestrial organisms (mammals, birds, reptiles and some invertebrates)

24

What is an adaptation to living on land?

internal fertilisation

25

Where is the ovum fertilised in internal fertilisation?

inside the body of the female

26

Do animals that lay eggs that hatch undergo internal or external fertilisation?

internal fertilisation (the actual process of fertilisation takes place inside the female's body)

27

What are some disadvantages of internal fertilisation?

there must be co-operation between the male and female so that the sperm can be placed inside the body of the female

28

What are some advantages of internal fertilisation?

not dependent on water
fewer gametes are produced
protection inside the body (drying out & predators)
gametes meet in a contained environment (greater chance of fertilisation)

29

Must organisms that have internal fertilisation be fed as they develops and grows?

yes

30

What are three strategies of internal fertilisation?

ovipary - animals lay eggs
ovovivipary - hatch in the body (or not long after being layed)
vivipary - give birth to live young