Heredity is the passing of traits
from parent to offspring.
Heredity is responsible for how you have your mother’s eyes and
your father’s smile. Along with this inherited similarity though, there is
also variation, as we are not exact clones of our mothers and fathers.
Offspring are the new organisms
produced by one or more parents.
(children, babies, young)
The study
of heredity
in biology
is called
genetics.
The Father of Genetics
Gregor Mendel was an Austrian
monk who studied mathematics
and science but became a
gardener in a monastery.
• Mendel thought there might be a
connection between the color of a pea
plant flower and the type of seed the
plant produced.
• He began to experiment with garden
peas in 1856.
• Mendel made careful use of
experimental design to study pea plants
and had the first recorded study of
how traits pass from one generation
to the next.
Reproduction
Reproduction - biological process by which
new "offspring" (individual organisms) are
produced from their "parents".
*It is the process by which an organism
produces others of its same kind.
Types of Reproduction
• Asexual - one parent
• Sexual - two parents
Asexual Reproduction:
a type of reproduction in which a new
organism is produced from one parent and has
the same DNA or genetic material as the parent.
Yeast cells dividing (budding)
Spider plant offspring
Asexual Reproduction
• Requires only one parent
• Offspring have 100% the same
chromosomes as the parent.
– In other words, the offspring are exact
“clones” of the parent.
– Mitosis
– Movie
Asexual Reproduction
Advantages:
• Animals that remain in one particular place and are unable to look for
mates would need to reproduce asexually.
• Numerous offspring can be produced without "costing" the parent a
great amount of energy or time. This type of reproduction is also faster.
• Environments that are stable and experience very little change are the
best places for organisms that reproduce asexually.
Disadvantages:
• Lack of genetic variation - all of the organisms are genetically identical
and therefore share the same weaknesses.
• If the stable environment changes, the consequences could be deadly to
all of the individuals.
*Animals are not the only organisms that reproduce asexually.
Yeasts, plants, and bacteria are capable of asexual reproduction as well.
Sexual reproduction:
a type of reproduction in which two cells,
usually an egg and a sperm, join to form a
new organism with its own genetic identity.
Animal
Plant
Sexual Reproduction
Advantage:
• Allows genetic variation within a species
which assists with the species survival
Disadvantages:
• Requires 2 parents
• Reproduction is slower
Sexual Reproduction
• All the members of the
Animal Kingdom
– Fish
– Mammals
– Amphibians
– Birds
– Reptiles
– Insects
– Crustaceans
Sexual Reproduction
• Examples of organisms that
reproduce sexually
– Chickens
– Iguanas
– Lobsters
– Sharks
– Humans
– Butterflies
– Sunflowers
– Roses
Sexual Reproduction
• Happens 2 ways
– Internally (inside)
• The egg is fertilized by sperm inside the female
– Mammals, birds, reptiles, insects, spiders
– Externally (outside)
• The egg is fertilized by sperm outside the
female
• The female lays the eggs and then the male
fertilizes them.
– Fish and some amphibians
– Plants and fungi (pollen and spores)
Asexual Reproduction
Examples
Asexual Reproduction
• Examples of organisms that reproduce
asexually
– Hydra
– Sea Star
– Strawberry
– Eubacteria
– Euglena
– Paramecium
– Yeast
Types of Asexual Reproduction
• Fragmentation
Fragmentation is where a
single parent breaks into
parts that regenerate into
whole new individuals.
Ex. Planaria
Types of Asexual Reproduction
• Vegetative Propagation
(Plant cuttings)
•
http://leavingbio.net/VEGETATIVEPROPAGATION.htm
Vegetative reproduction is a type of
asexual reproduction in plants where new
parts grow from parts of the parent plant.
It has long been used in horticulture and
agriculture.
Ex. Spider Plant
Types of Asexual Reproduction
• Binary Fission
– Bacteria
– Protists
Binary fission is a form of
asexual reproduction where
every organelle is copied and
the organism divides in two.
Types of Asexual Reproduction
• Budding
• Movie
Budding is where a
new individual
develops from an
outgrowth of a
parent, splits off, and
lives independently.
Types of Asexual Reproduction
• Regeneration
Regeneration occurs
when a body part has
broken off and the
organism grows a new
one. Ex. Lizard Tail
*The ability to restore
lost or damaged
tissues, organs or limbs