"Growth Period of Animals" PPT

Description

"Growth Period of Animals" PPT

Part One: Animal Reproduction Methods

Sexual reproduction: A method of reproduction in which sperm and egg cells combine to form fertilized eggs to produce new individuals.

Asexual reproduction: A reproductive method that produces new individuals directly from one mother without the need for the combination of sperm and eggs.

1. Diversity of sexual reproduction:

1) Different methods of fertilization

Thoughts and Discussions

1. Which of these two methods of fertilization is superior?

(It helps to increase the probability of fertilization)

2. In what environment do fertilized eggs formed by in vitro fertilization generally develop?

3. In animals with internal fertilization, the development of the embryo takes place inside the mother’s body?

2) Differences in embryonic development

—oviparous

-viviparous

—ovoviviparous

1. In addition to oviparous and viviparous, are there other types of embryonic development?

2. What are the differences between the three modes of embryonic development: oviparous, viviparous, and ovoviviparous?

Animal growth period PPT, part 2 content: Discussion:

1. The eggs of oviparous animals are much larger than those of viviparous animals. What does this mean for embryonic development?

The nutrients required by oviparous animals come from the yolk of the egg cell

2. What significance do viviparous and lactation have on the reproduction of mammals? Tell me why.

Viviparity and lactation greatly increase the survival rate of the next generation

Advantages of viviparous birth: warmth, safety, nutrition and oxygen guarantee

Advantages of breastfeeding: Breast milk is rich in nutrients and disease-fighting substances.

PPT on the growth period of animals, part three: diversity of reproductive methods

1. Diversity of sexual reproduction:

1) Different methods of fertilization

2) Embryos develop in different ways

2. Asexual reproduction: A reproductive method that does not require the union of sperm and egg cells, but directly produces new individuals from one mother.

Fission reproduction: a method of reproduction in which a mother body splits into two offspring

Budding reproduction: A reproductive method in which the mother gives birth to a bud at a certain location, and the bud grows up and falls off from the mother to develop into a new individual.

Animal growth period PPT, part 4 content: thinking

Who has more advantage, asexual reproduction or sexual reproduction?

The significance of sexual reproduction: offspring possess the genetics of both parents, have greater vitality and variability, and can adapt to changing environments.

The significance of asexual reproduction: Reproduction is fast and has advantages in a single and unchanged environment, but it is at a disadvantage when the environment changes.

Animal growth period PPT, part 5: practice

1. The starting point of animal ontogeny is ( )

A.Egg B.Fertilized egg C.Embryo D.Fetus

2. Which of the following environmental factors has the greatest impact on the development of fertilized eggs in oviparous animals ( )

A.Sunshine B.Air C.Moisture D.Temperature

3. Among the following animals, fertilization is completed in the body ( )

A. Locust B. Frog C. Crucian carp D. Toad

4. Distinguish the embryonic development methods of whales, geckos, turtles, giraffes, bats, domestic pigeons, alligators, mice and other animals:

Animals that lay eggs are: geckos, turtles, domestic pigeons, alligators

Animals that are viviparous are: whales, giraffes, bats, rats

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"The Growth Period of Animals" PPT courseware:

"The Growth Period of Animals" PPT courseware Part One: Animal Classification What are the five categories of animals from lower to higher? Fish, amphibians, reptiles, birds, mammals What are animals whose larvae are in water and adults are on land? Amphibians 1. According to the biology of frogs...

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Update Time: 2024-11-21

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