Download 6-3: Interactions Among Living Things (pg

1-3: Interactions Among Living Things (pg.1) Name __________________ Per. ____
Key Terms: Natural Selection/ adaptations/ niche/ competition/ predation/ predator/
prey/ symbiosis/ mutualism/ commensalisms/ parasitism/ parasite/ host(13 POINTS)
29 POINTS
I. Adapting to the Environment: (pg. 25)
Natural Selection:
A. ____________________ ____________________ is the process in which a
characteristic that makes an organism better suited to its environment and
becomes common in the species.
1. Individuals whose unique characteristics are best suited to their
environment tend to _______________ and produce ______________.
2. The offspring _____________________ these characteristics and
continue to reproduce.
B. Natural selection results in _________________, behaviors and
_______________ that make organisms live more successfully in their
environments.
C. Organisms with characteristics that are ______________ suited to the
environment are less likely to be successful and eventually ______________
from the species.
Niche
A. All organism has a variety of ______________ that make it suited to its
specific living conditions.
B. A ______________ is the role an organism takes to make its living.
1. A niche includes: the _______________ it eats, how it
______________ food, and how other organisms use it for
_____________.
2. A niche also includes ______________ and how an organism
reproduces and the ________________ _________________ it needs
to survive.
II. Competition: (pg. 26)
A. There are three major types of interactions among organisms:
_______________, ______________________, _________________
B. Different species can share the same _______________ and
_______________ requirements.
C. If 2 species share the same niche, one will eventually ______________ off.
D. The reason for this is _________________, the _______________ between
organisms to survive as they try to use the same __________________
resources.
E. In any ____________________ there is a limited amount of food, water and
__________________.
F. Organisms that survive have _________________ that enable them to reduce
_____________________.
1-3: Interactions Among Living Things (pg.2) Name __________________ Per. ____
25 POINTS
Predation: (pgs. 27-29)
A. The interaction where one organism kills another for ______________is
called _______________.
B. A ____________________ does the killing.
C. The victim of the predator is called the ____________________.
The Effect of Predation on Population Size
A. _____________________ can have a major effect on population sizes.
B. If a death rate exceeds the birth rate of a population, the population size
usually __________________.
C. If ____________________ are good at hunting the population size of the prey
________________________.
D. With less food for the predators, the predator population starts to
___________________.
E. Generally prey and predator populations _______________ and fall in related
_______________________.
Predator Adaptations:
A. Predators have ________________ that help them to catch and kill
________________.
1. Cheetahs can ______________ fast for short distances.
2. Jellyfish tentacles have a poisonous substance that ________________
tiny animals
3. The sundew plant is covered with ______________ _____________
that can snare a fly that lands on it.
4. Owl’s ___________eyes let much _______________ to help it see in
the dark.
5. Insect-eating bats produce pulses of ________________ and listen for
________________ to catch their prey in darkness.
Prey Adaptations:
A. Organisms have many _______________ that help them from becoming prey.
1. __________________ and ________________ help antelopes.
2. The ______________________________ of a skunk keeps predators
away.
1-3: Interactions Among Living Things (pg.3) Name __________________ Per. ____
41 POINTS
Look at Figure 16 on page 29 and list and describe the 5 defense strategies illustrated on the
page: 15 POINTS
1. ______________________:
______________________________________________________________
______________________________________________________________
2. ______________________:
______________________________________________________________
______________________________________________________________
3. ______________________:
_________________________________________________________________
_________________________________________________________________
4. _____________________:
_________________________________________________________________
_________________________________________________________________
5. _____________________:
_________________________________________________________________
_________________________________________________________________
Symbiosis: (Pgs. 30-31)
A. __________________ is a close relationship between 2 species that benefits at least
_____________ of the species.
B. There are 3 kinds of symbiosis: _____________________, _______________,
_______________________.
Mutualism:
A. The relationship in which both species benefit is called __________________.
B. In some cases of mutualism both species are so _______________ on each other that
neither could ________________ without the other.
C. Describe one of the 2 cases of mutualism listed in your text: 5 POINTS:
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
________________________________________________
Commensalism:
A. ____________________ is a relationship in which one species benefits and the other
is not _________________.
B. Commensalism is not very ________________ in nature because two species are
either helped or harmed a little by any interaction.
Parasitism:
A. ____________________ involves one organism living on or _______________
another and _________________ it.
B. The organism that benefits is call a __________________.
C. The organism that is harmed is called a _____________________.
D. Examples of parasites include __________________, _____________, and
_________________.
E. Unlike a predator, a parasite does not usually ______________ the organism it feeds
on.
F. If the host dies the parasite loses its source of ___________________.