Topic: Reproduction and development

Author Elżbieta Szedzianis

Target group

2nd‑grade students of high school

Core curriculum

I. Organization and chemism of life. Student:

8). it presents life activities of organisms.

General aim of education

The student acquires knowledge and skills about the topics discussed in the classes

Criteria for success

• explain what breeding is about;

• show differences between sexual reproduction and asexual reproduction;

• explain how simple development and complex development proceed.

Key competences

• communication in the mother tongue;

• communication in foreign languages;

• digital competence;

• learning to learn;

Methods/forms of work

talk.

Individual activity and activity in groups.

Teaching aids

• abstract;

• interactive or traditional board;

• tablets / computers.

Lesson plan overview

Before classes

Students get acquainted with the content of the abstract. They prepare to work on the lesson in such a way to be able to summarize the material read in their own words and solve the tasks themselves.

Introduction

1. The teacher explains the aim of the lesson, gives the subject and together with students determines the success criteria to be achieved.

2. The teacher plays the abstract recording for all students. Participants listen carefully and give feedback on the difficulty of the text being heard using the traffic light method. Students are provided with green, yellow and red cards. While listening to the recording, they display the appropriate color for self‑assessment and to inform the teacher:

• green - I'm fine, I understand everything;

• yellow - I have some doubts;

• red - I do not understand anything, please help. The teacher responds depending on the needs of the students, deciding to repeat the recording, listen to the recording while following the text or translate the text.

Realization

1. The students consolidate the acquired information, discussing it with their nearest neighbors („tell your neighbor” method).

2. The teacher uses the text of the abstract for individual work or in pairs, according to the following steps: 1) a sketchy review of the text, 2) asking questions, 3) accurate reading, 4) a summary of individual parts of the text, 5) repeating the content or reading the entire text.

3. Expanding and enriching English vocabulary in the issues covered in the lesson - students perform language exercises included in the abstract. The teacher makes sure that the tasks have been correctly completed and gives feedback.

4. Work of the whole class team. Students stand in a circle. The teacher encourages them to play: throws a ball or mascot to one of the students, saying the English word or notion learned in the lesson. The student gives the Polish equivalent, mentions another word in English and throws a ball or mascot to a friend or colleague.

Summary

1. The teacher chooses one student by random method and asks him or her to explain in own words the meaning of a given word or concept learned during the lesson.

2. At the end of the lesson the teacher asks: If there was going to be a test on the material we have covered today, what questions do you think would you have to answer? If the students do not manage to name all the most important questions, the teacher may complement their suggestions.

3. At the end of the class, the teacher asks the students questions:

• What did you find important and interesting in class?

• What was easy and what was difficult?

• How can you use the knowledge and skills you have gained today?

Willing/selected students summarize the lesson.

Homework

• Develop a lap book containing issues learned during the lesson and bring your work to the next class.

• Listen to the abstract recording at home. Pay attention to pronunciation, accent and intonation. Learn to pronounce the words learned during the lesson.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Reproduction and development

The life of each individual is limited in time. The species to which a particular individual belongs shall remain on Earth much longer than this individual. The species comprise all similar and related individuals living in the past and those that will live in future generations. Reproduction is a condition for the existence of the species, not for the existence of an individual, and generally leads to an increase in the number of individuals.

In the process of reproduction, organisms transfer genetic information to the offspring, i.e. specific instructions according to which the offspring will develop and function. There are two types of reproduction: asexual reproduction and sexual reproduction. Asexual reproduction leads to the formation of individuals very similar to the parental individuals, and sexual reproduction results in organisms with a much greater diversity of features than those of the parental individuals.

Asexual reproduction leads to the production of offspring which is formed of one parental individual and is almost an identical copy of it. This type of reproduction does not require a search for a breeding partner. Asexual reproduction may be beneficial for the species in case of nutrition abundance and absence of risks. When living conditions are stable, all organisms adapted to them can develop and reproduce without major obstacles, but under unfavourable living conditions, each of organisms with identical features is equally threatened with negative impact of the environment. If the parental individuals and the offspring react to temperature changes in the same way, they can die simultaneously in case of severe frost.

Many organisms reproduce asexually in nature. The simplest and quickest form of such reproduction is cell division into two daughter cells. Another way of asexual reproduction is budding, which occurs in some single‑cell fungi and aquatic organisms belonging to sedentary species. Fungi, moss and ferns reproduce by producing spores. Quite a common manner of asexual reproduction is body division (fragmentation), which occurs in part of plants, fungi, lichens, algae and in some animals. Plants reproduce asexually through the growth and division of aboveground or underground organs.

Sexual reproduction in animals usually takes place with the participation of two parental individuals. It is preceded by the formation of reproductive cells called gametes. Females produce female gametes, i.e. egg cell, males – male gametes, i.e. sperm. Fusion of the sperm nucleus and the egg cell nucleus is called fertilisation. As a result of this process, a new individual with an individual and unique set of features inherited from the parents is created.

Sexual reproduction therefore leads to the production of offspring similar to each other and to the parents, but with different features at the same time. The diversity of these features makes offspring have different chances of survival in case of changing environmental conditions. Therefore, even under very difficult conditions, some of the animals created as a result of sexual reproduction may be endowed with a feature useful in a given environment and have a higher chance of survival and reproduction. Most animals are dioecious, which means that a single individual is either a female or a male. However, there are species in which one individual produces both female and male gametes. Such organism is called a hermaphrodite.

Plants and fungi also reproduce sexually.

Animals can be fertilised in two ways. Internal fertilization occurs when the gametes are fused inside the body of the parental organism. In animals, it usually occurs during the act of copulation, in which the male introduces sperm into the female's genital tract by means of an intromittent organ. This type of fertilisation is characteristic mainly of terrestrial animals. External fertilisation takes place outside the body of the parental organisms, usually in aqueous environment. It consists in the secretion of gametes by males and females into the water. This usually happens at the same time and results from the mating activity of the animals. This type of fertilisation is found, for example, in most fish and amphibians.

Fusion of sperm and the egg cell leads to the formation of a zygote, from which embryo develops in multicellular organisms. During embryo development, many intense changes take place. All cells and organs of a multicellular individual are formed from a single cell, i.e. a zygote.

The process of embryo development requires a lot of energy. In some animals, the amount of nourishment necessary for embryonal development can be collected in egg yolks, in others it is supplied by blood vessels from the mother's organism. In case of animals producing a lot of eggs, these eggs generally contain small quantities of egg yolks. For this reason, the individuals that hatch from them are not fully developed. After hatching, they must prey on their own before they grow up. At this stage of development they are called larvae. The development during while the organism undergoes the larvae stage is called complex development. Animals which provide the embryos with a lot of nutrition during their development are characterized by a simple development, without the larvae stage.

In spermatophytes, the embryo develops in the seed – an organ filled with a reserve of nutrients – which is covered by the seed husk. Under favourable conditions, the seed sprouts and a new plant develops from the embryo.

• Reproduction is a condition for the existence of species.

• Reproductive cells (gametes) produced by parental organisms are involved in sexual reproduction.

• Thanks to sexual reproduction, the individuals differ from each other, which increases the chances of the species survival.

• As a result of asexual reproduction, many offsprings produced from the same parental organism are substantially similar in genetic terms to the parental organism and to each other.