Water Cycle Grade 4 Worksheets – Students are taught about the life cycles of different creatures. A butterfly’s lifecycle can be compared with that of a shark. They can also learn about the life cycle of an amphibian. This worksheet can help students learn how animals live. The worksheet can be completed by students individually or in a group.
The life cycle of a human
Fertilization is the moment when an egg cell from a woman merges with a male sperm cell. This begins the human life cycle. On the sixth day, the single cell divides into a series of smaller ones that burrow into the mother’s womb. These cells begin to form three layers and then bend into an embryo. In this stage, they also begin to differentiate from one another and form the fetal nervous system and circulatory system.
During this period, the human brain and body undergo many changes. Although some differences exist between humans and apes, the basic life cycle of both is the same. For example, humans develop an erect body and show off their movable hands, whereas apes develop great cognitive talents. The food we eat supports a host of changes in the human body and brain after conception.
A human life cycle is structured around a series of developmental stages and age groups. It also includes an infancy period. A human’s average life expectancy is approximately seventy-eighty years. However, this can vary depending on their health.
Life cycle of a butterfly
The egg is the first step in the life cycle of a butterfly. This egg contains the nutrients the caterpillar needs to survive. Most butterflies lay eggs on leaves. The eggs are small and may be round, oval, or cylindrical in shape. Monarch butterflies lay their eggs on the underside of plant leaves. They can be either smooth or wrinkled. Within a few weeks, the eggs will hatch.
Once the butterfly has emerged from the pupa, it pumps its blood into its wings. Within a few hours the wings will be fully developed and the butterfly can fly. Once the wings have grown, the butterfly will search for food and a mate. Once it has found a mate, it will lay eggs on a leaf.
The next stage is the adult stage. The butterfly lays eggs every year in spring, summer and fall. A large number of eggs can be laid by a female butterfly at once. Although the eggs are small, they can be very large. The egg is the basis for the development of the caterpillar (also known as the larva). It eats continuously during this period and sheds its skin up to five times. It also stores food, which will be used by the adult butterfly.
Life cycle of a shark
Sharks have an extremely long life cycle. Sharks can live up to 15 years. Sharks are most commonly born near the coast and stay close to their birthplace until they reach adulthood. During this time, sharks grow, mature, and reproduce. Two claspers allow sharks to grasp onto females and insert sperm.
Female sharks incubate the eggs and sperm for a period of several months until they reach full term. The mother keeps the young sharks inside for about a year before they are born. Some species of sharks exhibit cannibalism, where the first pup is born alive and eats other eggs or pups. The gestation period of these ovoviviparous species varies, but it is often several months to two years. Some species are also known to reproduce through asexual reproduction.
Sharks are extremely sensitive to sound waves and have exceptional hearing. Their two sets of dorsal fins are located on either side of their heads. Their lateral line system consists of thin canals filled with water and is attached to nerves that send signals to the brain.
Amphibian life cycle
The life cycle of most amphibians is complex, with a larva becoming an adult and then a larva becoming a larva. These life cycles are governed by hormones and the environment. Thyroid hormones and corticosteroids produced by interrenal glands are the primary morphogens in amphibians and are dependent on input from the hypothalamus and pituitary glands. Ultimately, the hypothalamus regulates the activity of both the thyroid gland and the pituitary gland.
Amphibians have unique life cycles and a unique ability to reproduce in two environments – on land and in water. A frog’s life cycle begins with sexual reproduction. This is when the male lures the egg-carrying women to mate. The females then release their eggs into the water where the males fertilize them with sperm. Most species of amphibians reproduce by external fertilization.
Most species of frogs lay their eggs in peaceful water, which protects them from predators. However, some species stay with the eggs to care for them. Once fertilized, the eggs begin to split into more cells, taking on the form of a tadpole. The tadpoles hatch within one to three weeks.