Mammals

Mammals are endothermic vertebrates. They are the only animals with fur or hair on their body, and ear flaps. Most mammals are placental mammals.

This means that their young develop inside the mother's uterus, nourished by an organ called the placenta. The umbilical cord connects the young to the placenta.

After birth, young mammals drink milk from their mother's mammary (milk-producing) glands until they are old enough to eat the adult's diet.

Milk is the ideal food for a young mammal: it contains all the nutrients that it needs for growth and development.

9. Read the text and answer the questions.

Plants

Most plants are green because they contain the substance chlorophyll. They use it to trap light energy; this is used during photosynthesis to make food. Plants are usually anchored in a growing medium such as soil. Some, such as mosses and liverworts, are small and delicate. Others, such as the giant redwood trees are huge. Many plants, such as marigolds and sunflowers, are annuals, which mean that they live for just a year. Perennials can live for many years: some bristlecone pine trees, for example, are 5,000 years old.

1. Why are most plants green?

2. What for do they use chlorophyll?

3. What small and big plants do you know?

4. What are annuals and perennials?

Read the text and get ready to ask 5 questions on it.

Nonflowering Plants

Plants that do not use flowers for reproduction include conifers, ferns, mosses, and seaweeds (the last are not true plants). Conifers reproduce by means of cones. A male cone is usually smaller than а female cone, and both are usually carried on the same tree. Conifers have needlelike leaves, whose small surface area prevents the plant losing too much water. This helps conifers survive in the cold, dry places they often live in. Many conifers are evergreen - they do not shed their leaves in the fall.

11. Read the text find English equivalents to the Russian words and expressions:

1. Лепестки, 2. опыление, 3. оплодотворение, 4. разбрасывание семян, 5. однодольные, 6. двудольные.

Flowering Plants

Using flowers to reproduce is so efficient that flowering plants are the most widespread of all ants. Flowers carry the reproductive organs within a ring of petals. After pollination and fertilization, the flowers produce seeds, which are enclosed and protected by fruits. These have clever ways of scattering their seeds. Some flowering plants, such as maize, make seeds in one part; they are monocots. Others, such as bean plants, make seeds in two parts; they are dicots.