2nd Grade Science Worksheets Water Cycle – Students learn about the different life cycles of various creatures. For example, a butterfly’s life cycle can be compared to the life cycle of a shark. Students can also learn more about the life cycle and habits of amphibians. This worksheet will help students understand how animals live. The worksheet can be completed by students individually or in a group.
Life cycle of a human
The human life cycle begins at fertilization when the egg cell of a woman fuses with a sperm cell of a man. The sixth day is when the single cell splits into several smaller cells that burrow into the mother’s womb. These cells form three layers and begin to bend into a complex shape called an embryo. In this stage, they also begin to differentiate from one another and form the fetal nervous system and circulatory system.
The human body and brain undergo a number of changes during this time. While there are some differences between humans and apes in their lives, they all follow the same basic cycle. Apes, on the other hand, have a more erect body that allows them to show off their mobile hands. 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 infant phase. A human’s average life expectancy is approximately seventy-eighty years. However, this can vary depending on their health.
The life cycle of a butterfly
The egg is the first step in the life cycle of a butterfly. The caterpillar’s needs are met by the egg. Most butterflies lay their eggs on leaves. The eggs can be small, round, oval or cylindrical. 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. After a few hours, the wings will fully develop and the butterfly will begin to fly. After the wings are fully developed, the butterfly will begin to search for food and a partner. After finding a mate, the butterfly 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. The eggs may be small. The caterpillar, also known as the larva, develops from the egg. 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 live a very long life span. They can live for up to fifteen years. Sharks are most commonly born near the coast and stay close to their birthplace until they reach adulthood. Sharks mature, reproduce, and grow during this period. 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. Cannibalism is a behavior in which a shark’s first pup is alive and eats other pups or eggs. The gestation period of these ovoviviparous species varies, but it is often several months to two years. Asexual reproduction is also possible in some species.
Sharks have excellent hearing and are able to detect incoming sound waves from their prey. 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. The primary morphogens of amphibians are thyroid hormones and corticosteroids, which are produced by interrenal cells. They are dependent on inputs from the hypothalamus as well as the pituitary and pituitary. The hypothalamus controls the activity of the thyroid and pituitary glands.
Amphibians have unique life cycles and a unique ability to reproduce in two environments – on land and in water. The life cycle of a frog begins with sexual reproduction, in which the male entices the egg-carrying females 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. Some species, however, stay with the eggs to care. 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.