33.1 Characteristics of Animals

• The key characteristics of multicellular animals are listed.
• Animals lack cell walls and are flex other organisms.

• This flexibility makes it possible to move.
• An overview of the history of animal life on Earth is required.

• The Earth contains a dazzling diversity of animal species, living in ally, a group of unique cell junctions--anchoring, tight, and gap junc environments from the deep sea to the desert and exhibit an amaz tions--play an important role in holding animal cells in place Most animals are able to communicate with each other by moving and eating multicellular.

• A number of key features can be used to make drugs.

• The production of enzymes from other organisms is what distinguishes fungi and animals from each other.

• Animals break down their food by taking it into their internal gut.

• Sponges are multicellular and can move from place to place in order to get food or escape predators.
• The ability has single-celled organisms called protists.

• Animals get their food by eating other sory structures and a nervous system that coordinates movement.
• This is different from prey capture.
• Sessile species such as barnacles, which stay in one place, plants and algae, most of which are autotrophs use bristled appendages to obtain nearby food.
• Many people make their own food.

• Most protists have a rigid cell wall, but animal cells lack it and are flexible.

• Most animals have a nervous system that allows them to reproduce asexually.

• Most animals have a muscle system.
• Fertilization may occur internally, which is common, combined with a nervous system, which allows them to move in their environment.

• In sexual reproduction, most animals reproduce sexually with small environments.

• The history of animal life begins at junctions called anchoring, tight, and gap junctions.

• Special clusters of most animals have Hox genes, which function in mals without a spine.