How many eggs are produced in internal fertilization?
There are three ways that offspring are produced following internal fertilization: oviparity, ovoviparity, and viviparity. In oviparity, fertilized eggs are laid outside the female’s body and develop there, receiving nourishment from the yolk that is a part of the egg.
Why do you think the eggs are found in the water where do you think fertilization happens?
External fertilization in animals usually occurs in water or in damp areas in a process called spawning. Moisture in the environment keeps the gametes from drying out. Moisture is also important so the eggs and sperm can move around freely, which lets them meet and fuse.
How does fertilization occur in animals?
In animals, the process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo. Depending on the animal species, the process can occur within the body of the female in internal fertilisation, or outside in the case of external fertilisation.
What is the site of fertilization in animals?
Fertilization depends upon the two gametes bumping into one another. In species with internal fertilization, which includes all mammals and birds, both sperm and egg must be transported into the oviduct, which serves as the site of fertilization.
How animals grow and develop?
The primary way that animals grow and develop is by building more cells. When an animal eats food, its body breaks the food down and uses it to fuel its energy requirements and build new cells through the process of mitosis. To produce more cells, animal cells divide in two.
What causes animals to grow?
The food that animals eat can be transformed into usable energy for cells or can be used to build new cells, which form tissues like skin and muscle. The process of growth involves eating food, breaking down food through digestion, absorbing nutrients from food, and building tissue.
What can we learn about animals as they grow and change?
Main Idea Animals go through changes as they live and grow. Death The animal’s life ends. Some animals, such as people, get larger as they grow older. Unlike people, some animals go through life cycle changes called metamorphosis (met.
How are animals formed?
Animal development, the processes that lead eventually to the formation of a new animal starting from cells derived from one or more parent individuals. Development thus occurs following the process by which a new generation of organisms is produced by the parent generation. …
Where did all animals come from?
Genetic data suggest that multicellular animals evolved around 1000 million years ago; this is supported by fossil embryos from rocks in China that date back 600 million years.