It is thigmotropism because it is not affected by gravity or light.
Answer:
Radiometric dating methods
Explanation:
Absolute dating is the process of determining an age on a chronological or specified time scale in which events occurred in archaeology and geology. Absolute dating can be determined by using properties of the atoms that make up materials.
The most common method of absolute dating uses by geologists is radiometric dating methods which is based on the natural radioactive decay of certain elements such as potassium and carbon found in the rocks. By comparing the ratio of parent isotope with a known half-life to daughter product in the rock, the age of the rock can be determined.
The carbon-14 isotope is used in radiocarbon dating, but is only useful for measuring recently formed rocks in the geologic past. The decay of Potassium-40 isotope known as potassium-argon (K-Ar) method allows dating of materials that up to 1,000 billion years old.
Answer:
e. cutin
Explanation:
Plant exhibit many variations to withstand the temperature variations, desiccation and increased UV exposure which are some of the factors associated with land habitat. Cutin is a waxy substance that is found in the outer walls of the epidermal cells of plants. Cuticle in plants serves to make the outer most covering of aerial parts of the leaves and non-woody stem of herbaceous plants. The cuticle is made of cutin.
Cutin serves to protect the plant’s aerial surfaces from excess water loss. It also filters the excess UV light and thereby protects the underlying plant parts. The thickness of the cuticle varies in different plants depending upon the environmental conditions. The leaves of plants adapted to hot, dry climates have thick cuticles. The thickness of the cutin layer also varies in different parts of a plant. For example, the upper epidermis of leaf generally has a thicker cuticle than the shaded and relatively cooler lower epidermis.