Answer: It was obtained 8515 years ago
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) to find the rate constant:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
b) for completion of 36% of reaction
t = 8515 years
The time was 8515 years.
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.
Meiosis produce cells with half the chromosomes, because a<span> gamete needs only half the number of chromosomes, because two gametes join together. </span>
Since two females are unable to reproduce. Therefore, if only two females are still alive, the species will become extinct.
