Survival Success

Passage 1:

Place the letter of the appropriate structure from the amniote egg diagram into the following passage.

The amniote egg is one of the major advances that enables vertebrates to more from the water onto land. Fish and amphibian eggs must remain in water to prevent dehydration. The amniote egg is surrounded by a shell (1 _____) to protect the developing embryo from dehydration.

The embryo (2 _____) is surrounded by a sac formed by the amnion (3 _____), which holds embryonic fluid. This fluid protects the developing embryo from shock.

Another membrane-enclosed sac called the allantois (4 _____), stores harmful nitrogen waste products formed by the developing embryo. These metabolic waste products are kept away from the embryo as it grows, keeping the embryo's environment clean and safe.

Food for the developing embryo is provided by the yolk. The yolk is an protein-rich fluid surrounded by a membrane to form a yolk sac (5 _____).

The shell is lined by a membrane called the chorion. this membrane regulates movement of gases in and out of the shell. There is an air space (6 _____) at the rounded end of the egg, providing an area of gas exchange with the inside and outside of the egg.

Passage 2:

Use this passage to answer the next set of questions.

Ectothermic animals have a body temperature that is determined by their environment. Most reptiles are ectothermic, moving back and forth between sunlight and shade to control their body temperature. Mammals and birds are examples of endothermic animals, whose body temperature holds at a constant level.

Endothermic animals need more energy to maintain their constant body temperature, making them more active. Since ectothermic animals use energy more slowly, they feed less often than endothermic animals. Some snakes may feed only three or four times in a year.

Because of the high energy requirements of flight, birds have the highest metabolic rate of all animals. It is not uncommon for birds to eat an equilivant of their body weight every day. The shrew is the only mammal with a metabolic rate requiring such large amounts of food.

7. An example of an ectothermic animal.

1. human
2. sparrow
3. snake
4. fox

1. ectothermic
2. cold-blooded
3. metamorphic
4. endothermic

1. bass
2. snake
3. shrew
4. none of these

1. birds
2. mammals
3. amphibians
4. fish

Use this passage to answer the next set of questions.

Based on how embryos develop and are nourished, there are three different reproductive strategies. Oviparous animals produce amniote eggs and lay them in a nest for incubation. When the eggs hatch outside the nest, the young must find or be given food if they are to survive. Examples of oviparous animals include birds and most reptiles.

Ovoviviparous animals produce amniote eggs, but carry them inside the body of the female until they hatch. When the young leave the body of the female, they must find or be given food if they are to survive. Several snakes are ovoviviparous.

Viviparous animals do not produce amniote eggs. The young develop inside of, and receive nourishment from the body of the female. The only mammals that are not viviparous are the duck-billed platypus and spiny anteater. Both of these mammals lay amniote eggs, but the mother's body produces milk to nourish them after they are born.

11. An animal that lays eggs in a nest and produce milk to nourish the young.

1. birds
2. spiny anteater
3. snakes
4. kangaroos

1. marsupials
2. oviparous
3. ovoviviparous
4. viviparous

1. do not produce amniote eggs.
2. nourish their young with milk.
3. are ovoviviparous.
4. none of these