Lifecycle of Living Things

Grade 8 Science Worksheets

Home | 8th Grade Science Worksheets | The lifecycle of Living Things

Schedule a Free session to clear worksheet doubts

Loading...

 

Introduction

Living things go through a sequence of changes from one form to another and from one generation to another, in the process of growth and reproduction. Mammals, for example, develop from a fertilized egg to an adult. Adults then produce new sex cells, known as gametes, which fertilize new egg cells to initiate the same development process again. This specific and repeated pattern of developmental stages is called the Lifecycle of that organism. All plants and animals undergo a lifecycle unique to them. Two important lifecycles are explained here.

Schedule a Free session to clear worksheet doubts

No credit card required, no obligation to purchase.
Just schedule a FREE Sessions to meet a tutor and get help on any topic you want!

Plant Lifecycle

Flowering plants and trees start life as a seed which contains the embryo and a protective layer. A seed needs fertile soil to germinate by breaking the outer layer and growing roots, shoots, and leaves. This is the beginning of a new plant or tree, known as a seedling. When the plant has grown to maturity it grows flowers. Male flowers contain pollen and female flowers have ovaries. Natural elements, like the wind or bees, carry the pollen from one flower to the ovary of another flower and start the process of pollination. The cells in the ovary (ovules) are fertilized and new seeds are produced. These seeds get dispersed by wind, water, animals to new soil where the process of germination starts afresh.

Non-flowering plants, such as moss or fern, don’t produce seeds. They produce spores which get carried by the wind to new moist soil to begin life after germination.

Insect Lifecycle – Metamorphosis

Insects – houseflies, moths, butterflies – undergo transformation through strikingly distinct stages from an egg to adulthood. Typically, this is a four-stage process called a Metamorphosis.

  1. The egg
  2. The larva or caterpillar
  3. The pupa or chrysalis
  4. The adult

The lifecycle begins with the egg in which the embryo forms. These insects lay eggs on plants or on decaying organic matter which provides food for the next stage of development, called the larva. In butterflies and moths, the larva is also known as a caterpillar, while in houseflies it is referred to as a maggot. A larva is simply a fleshy worm-like creature, with or without hair, and with a sucking mouth. They have no wings.

The larva grows rapidly and sheds its outer skin many times, called molting, to reach the third stage in which it attaches itself to a twig and spins a cocoon around itself. This stage is known as the pupa or the chrysalis stage. The pupa may be silken in nature as with most moths and butterflies, or it may simply be a hard, protective shell as in the case of houseflies. Inside the chrysalis, a rapid and dramatic transformation takes place – the final metamorphosis!

Personalized Online Tutoring

eTutorWorld offers affordable one-on-one live tutoring over the web for Grades 2-12, Test Prep help for Standardized tests like SCAT, CogAT, SSAT, SAT, ACT, ISEE and AP. You may schedule online tutoring lessons at your personal scheduled times, all with a Money-Back Guarantee. The first one-on-one online tutoring lesson is always FREE, no purchase obligation, no credit card required.

For answers/solutions to any question or to learn concepts, take a FREE Demo Session.

No credit card required, no obligation to purchase.
Just schedule a FREE Sessions to meet a tutor and get help on any topic you want!

The larva or caterpillar grows wings, limbs, tissue, and all the beautiful colors of an adult butterfly or moth. It emerges by breaking the shell of the pupa and after resting awhile it slowly starts flapping its wings to become a fully developed adult. The adult then goes on to find a mate and repeats the process of laying eggs and having them fertilized to form a new lifecycle.

Check Point

  1. The process of growth and development from egg to adult in any living organism is known as its ______.
  2. Put in the correct order the flowering plant stages –
    1. Flowering
    2. Germination
    3. Seedling
    4. Pollination
  3. Non-flowering plants do not produce ______, they produce ______ instead.
  4. Put in the correct order the metamorphosis stages –
    1. Larva
    2. Adult
    3. Chrysalis
    4. Egg
  5. Other words for larva in butterflies and houseflies are ______ and ______ respectively.

Answer Key

  1. Lifecycle
  2. Germination, Seedling, Flowering, Pollination
  3. Seeds, Spores
  4. Egg, Larva, Chrysalis, Adult
  5. Caterpillar, Maggot

Schedule a Free session to clear worksheet doubts

No credit card required, no obligation to purchase.
Just schedule a FREE Sessions to meet a tutor and get help on any topic you want!

Pricing for Personalized Online Tutoring

Tutoring Package Validity Grade (1-8) Grade (9-12), College
New Student Special (5 sessions) 1 Month $89 $99
1 session 1 Month $22 $24
5 sessions 3 months $104 $114
10 sessions 3 months $199 $219
15 sessions 3 months $289 $319
20 sessions 4 months $379 $409
50 sessions 6 months $899 $949

©2020 eTutorWorld           Terms of use            Privacy Policy            Site by Little Red Bird          

©2020 eTutorWorld
Terms of use
Privacy Policy
Site by Little Red Bird