Grade 8 Science - Plant Biology, Photosynthesis, and Life Cycles

Vocabulary practice flashcards generated from the Grade 8 Science test paper covering photosynthesis, transpiration, transport in plants, metamorphosis, and pest control.

Transpiration

The process of evaporation of water through a plant, occurring during daytime where water is released in water vapour form.

Guttation

The release of water from a plant in liquid form, occurring at night time.

Metamorphosis

The process involving different morphological changes across different stages of an organism's life cycle.

Complete Metamorphosis

A form of metamorphosis involving $4$ distinct stages in the life cycle, such as in butterflies.

Incomplete Metamorphosis

A form of metamorphosis involving $3$ stages in the life cycle, such as in grasshoppers.

Butterfly Life Cycle Stages

The $4$ stages of a butterfly's life cycle: Eggs, Caterpillar (Larva), Pupa, and Adult butterfly.

Nutrition Mode of Frogs vs. Tadpoles

Frogs eat insects in the atmosphere, whereas tadpoles eat insects in the water.

Raw Materials for Photosynthesis

Carbon dioxide and water.

Main Product of Photosynthesis

Glucose.

Internal Factor for Photosynthesis

Chlorophyll.

Stomata

The plant structures through which carbon dioxide and oxygen gases are exchanged by diffusion.

Transpiration Pull

The pulling force that helps plants absorb water from the soil.

Photosynthesis Word Equation

$$\text{Carbon dioxide} + \text{Water} \xrightarrow{\text{Sunlight}, \text{Chlorophyll}} \text{Glucose} + \text{Oxygen}$$

Sucrose

The form in which the products of photosynthesis are transported to other parts of the plant.

Phloem Tissue

The tissue through which products of photosynthesis (sucrose) are transported throughout the plant.

Global Importance of Photosynthesis

Produces oxygen required for respiration and helps in controlling global warming.

Osmosis

A process of water transport across a semipermeable membrane, as demonstrated by an increase in the level of sugar solution.

Artificial Semipermeable Membrane

Cellophane.

Natural Semipermeable Membrane

The thin layer in a boiled egg membrane.

Factors Affecting Transpiration Rate

Temperature and humidity; high temperature increases transpiration rate, while low humidity or high humidity affects the rate inversely.

Plant Advantage of Transpiration

Cooling the plant.

Pumpkin Epidermal Adaptation

Hairs in the epidermis that help minimize water loss from transpiration.

Biological Pest Control

Controlling a pest population through the use of another organism that depends on or feeds on the pest.

Advantage of Biological Pest Control

It is eco-friendly and easy to manage.

Disadvantages of Chemical Pest Control

Pollution of soil and death of animals favourable to plants.

Fruit Fly Control Step

Destroying fallen fruit that has been infected by the fruit fly.

Importance of Learning Life Cycles

Helps control human disease vectors, manage pests, and promote the conservation of biodiversity.