Types of Animals and Their Interdependence

1) What Is a Brood Pouch? Give an Example of an Animal Which Has a Brood Pouch on Its Body.

• A brood pouch, also called the marsupium, is a bag-like structure found in marsupials.
• It is an additional fold of skin that makes a bag-like structure and allows the offspring to enter and live in it until it is mature enough.
• The marsupials are characterised by premature birth, where the offspring are not strong enough to survive. Hence, this brood pouch helps in their protection.
• The pouch is located at the lower belly of the animal. It allows the offspring to attach to the nipples of the mother’s body.

2) What Is the Meaning of Vectors? Give Examples.

The organisms that help spread the disease by spreading its causal organism are called vectors.

Examples of vectors are as follows—

• Female Anopheles mosquito spreads a causal organism of malaria.
• The Aedes mosquito spreads the causal organism of dengue.
• Houseflies spread the causal organisms of typhoid, jaundice and diarrhoea.

3) How Do Gills Help in Respiration?

The organisms that help spread the disease by spreading its causal organism are called vectors.

• Gills are present in some larval forms of amphibians and in fish.
• The gaseous exchange in gills occurs through the thin membrane that covers the gills.
• The carbon dioxide-rich blood is transferred to the gills. Carbon dioxide and oxygen get exchanged when the oxygen-rich water drains the gills.
• Carbon dioxide is released, and oxygen is absorbed.

4) What Are the Functions of the Lateral Lines in a Fish?

• The lateral lines are present as faint lines of tiny pores from the gill covers to the base of the tail of a fish.
• It is a group of sensory organs which are sensitive to touch.
• These sensory organs help detect the movements and pressure changes in surrounding water.

5) Name an amphibian that has gills.

The Axolotl salamanders are amphibians predominantly found in Mexico that have external gills.

6) What Is the Difference Between Vertebrates and Invertebrates?

• The animals with a backbone, also called the vertebral column, are called vertebrates, such as snakes, amphibians, fishes, reptiles, birds, mammals, etc. The body of a vertebrate can be divided into two equal halves.
• The animals which do not have a backbone are called invertebrates, such as worms, insects, starfish, etc. An invertebrate's body can be divided into two equal halves or more than two equal halves.