Growing before birth
Embryo in birds and mammals.
Chick and calf
A chick grows in an egg. A calf grows inside its mother.
What is the early growing stage called?
What this lesson covers
The idea
In birds the female lays the fertilised egg, stocked with food, and the embryo develops outside her body until hatching; in most mammals the embryo develops inside the mother, whose body supplies food and oxygen.
Chick and calf
A chick grows in an egg. A calf grows inside its mother.
What is the early growing stage called?
- Embryo
- Gamete
- Seed
Two ways to grow
Open each tab.
Embryo
After fertilisation, the fertilised cell grows into an embryo. In birds the embryo develops in an egg. In mammals it develops inside the mother's body.
After fertilisation the cell grows into an embryo. Birds: in an egg. Mammals: inside the mother.
Notes
Embryo: in birds inside an egg; in mammals inside the mother.
Check yourself
The early stage after fertilisation is the …
In birds the embryo develops in …
In mammals the embryo develops …
A cow is a …
- gamete. A gamete is a reproductive cell.
- embryo — correct. Yes!
- seed coat. The embryo is the early stage of life.
- the soil. In birds the embryo grows in an egg.
- water only. In birds the embryo grows in an egg.
- an egg — correct. Yes!
- inside the mother's body — correct. Yes!
- in an egg outside the body. That is in birds.
- in a nest. In mammals the embryo develops inside the mother.
- bird, so its embryo grows in an egg. A cow is a mammal.
- mammal, so its embryo grows inside the mother — correct. Yes!
- plant. A cow is an animal.