Download Reproduction Notes:

Reproduction Notes:
There are two main types of reproduction, _______________ and _______________.
Asexual reproduction:
 The process by which offspring are formed __________ the __________ of an egg
and sperm.
 Only ___________ individual is involved in the process.
 There are many different forms such as: ______________, ____________ and
______________.
 Organisms that reproduce asexually do __________ have a gender or sex organs.
For example: There are _____ male and female bacteria….just bacteria.
Asexual reproduction has several advantages:
1. ___________ animals (animals that CANNOT move) can reproduce without
finding a mate.
2. Allows the production of ___________ offspring in a short period of time b/c
all individuals in a population reproduce.
Drawback of asexual reproduction:
o All of the offspring are _____________ (identical in DNA), so if conditions
change and they are no longer well adapted to their environment, there is a
good chance that all or most will die.
Types of Asexual Reproduction:
o Budding: occurs when a new individual develops on the ___________ of
the parent. The ____________ may stay attached or ___________ off to
begin an independent life.
o Binary Fission: involves the separation of a parent into ___________ or
more individual of approximately the same ______________.
o Fragmentation or Regeneration: the ____________ apart of an organism
into several pieces. Each piece re-grows (regenerates) the missing parts
and develops into a new ______________.
Sexual reproduction:
o The process by which offspring are formed by the fusion of egg and sperm to
form a diploid (contains ____ copies of each chromosome) ____________.
o ______________ = fusion of egg and sperm
o Offspring receive ___________ of their DNA from each parent.
o Offspring are __________________ ______________.
o This type of reproduction increases the genetic diversity of the species. It is
______________ in environments that are under constant stress.
Drawbacks of sexual reproduction:
Have to find a _________
Have to wait until sexual _________
Not all members of the population ____________
Major Mechanisms of Fertilization:
External Fertilization:
 Eggs are shed into the _________________________ and fertilized by the male.
 Occurs in moist habitats where development can occur without the fear
of__________________
_____________________
 The process can occur without ________________________ between the parents.
 Chemical signals coordinate the process insuring the gametes are not
____________________.
Internal Fertilization:
 Occurs when sperm are deposited in or near the __________________ reproductive
tract and fertilization occurs __________________________ the female body.
 Requires a more ___________________________ reproductive system and
cooperative mating behaviors.
Embryo Development:
o Embryos
o Internal
can develop _________________ or ________________.
development means that the embryos develop ____________ the body of the
mother.
o In
order for internal development to occur, there had to have been ____________
fertilization.
o Animals
that follow this development pattern are referred to as having “_________
_________”.
o Embryos
may also develop externally, or _____________ the body of the mother.
o External
development may happen after either ___________ or ______________
fertilization.
Embryo Protection
Externally produced embryos are protected in several ways:
 They may be covered with a __________________________________ which allows
for free gas exchange with the environment and provide the embryo with moisture.
 _____________________ numbers of zygotes are produced to insure that some
reach maturity.
Internally produced embryos:
 May be protected by an egg shell, as in reptiles and birds. Some are ____________
and some are ____________.
 ___________________ mammals retain their offspring in a special structure called
the uterus.
 Internally protected zygotes have a ___________ rate of survival, and therefore,
fewer ____________ are produced.