Nitrogen Cycle Worksheet Key 7th Grade – Students learn about the different life cycles of various 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
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 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. Apes, on the other hand, have a more erect body that allows them to show off their mobile hands. A human body and brain undergo a variety of changes after conception, which are supported by the food we eat.
A human life cycle is structured around a series of developmental stages and age groups. It also includes an infant phase. The average life span of a human is about seventy to eighty years, but this can vary widely depending on the health of the individual.
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 eggs on leaves. The eggs can be small, round, oval or cylindrical. Monarch butterflies lay their eggs on the underside of plant leaves. They may be smooth or wrinkled. The eggs hatch within a few weeks.
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. 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). During this time, it eats continuously and sheds its skin four or five times. It also stores food, which will be used by the adult butterfly.
Sharks live a long life
Sharks have an extremely long life cycle. Sharks can live up to 15 years. Most sharks are born in coastal areas and remain close to the area where they were born until they are fully grown. Sharks mature, reproduce, and grow during this period. Two claspers allow sharks to grasp onto females and insert sperm.
The eggs and sperm are incubated by female sharks for several months before 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. Some species are also known to reproduce through asexual reproduction.
Sharks are extremely sensitive to sound waves and have exceptional hearing. The dorsal fins on their heads are located on either side. The lateral line system is made up of narrow canals filled with water that are attached to nerves that transmit signals to the brain.
Amphibian life cycle
Most amphibians have a complex life cycle, starting as a larva and ending as an adult. Hormones and the environment control these life cycles. 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 are unique in their life cycles. They can reproduce in both water and on land. The life cycle of a frog begins with sexual reproduction, in which the male entices the egg-carrying females to mate. The females release their eggs into water, where the males fertilize with sperm. Most species of amphibians reproduce by external fertilization.
Many species of frogs lay eggs in calm water which protects them against 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. Within one to three weeks, the tadpoles are ready for hatching.
Gallery of Nitrogen Cycle Worksheet Key 7th Grade
