Question

The Cambrian Explosion is famously known for it being the time period in which there was a Gradual decrease in the number of mammal species Rapid increase of 96 of the mater marine species Extinction of reptilian species such as the dinosaurs Sudden and dramatic increase in diversity of animals and plants QUESTION 31 The carbon cycle is important because carbon is a major ingredient for all organic molecules. What can cause disturbances to the carbon cycle? Methane gas released by organisms such as cows Burning of wood and fossil fuels Planting trees and other plants Cellular respiration by aerobic organisms QUESTION 32 The human population has been growing and is reaching a total population of 78 billion individuals. Which population growth model best represents the growth of the human population? K-selected R-selected Logistic Exponential QUESTION 33 The portion of the ocean that light penetrates is called Aphotic zone Photic zone Intertidal zone Pelagic zone

Answer 1

Ans. 30) sudden increase in diversity of animal and plants.

The Cambrian period is also known as the Cambrian explosion because a sudden increase in animal phyla was observed. From this period scientists get fossils of diverse organisms and also some of them are still alive.

Most of the marine species were at Permian period. Dinosaurs were extinct at the end of the Cretaceous period.

Ans. 31) Burning fossil fuels and wood.

The carbon cycle can be disturbed by burning fossil fuel because it releases the underground carbon, stored for millions of years, in the form of carbon dioxide, a greenhouse gas.

Rest three option doesn't disturb the carbon cycle.

Ans. 32) Logistic

Logistic growth show S shape curve. The organisms first grow slowly known as lag phase then growth increase suddenly known as the exponential phase. When the population reaches carrying capacity, growth slows and produce S shape curve.

Exponential growth is where the population grow exponentially, which is not true for the human population. R selection growth is where the population reproduce once in a lifetime and a high number of child and there is no parental care. Humans are K selected species, but for the human population,n k selection growth is the t best model because humans can show exceptions in different conditions.

Ans. 33) Photic zone

The photic zone is the upper layer of the ocean of up to 200m where light penetrates and therefore the maximum amount of photosynthesis and more number of life is observed in this zone.

The aphotic zone where light does not penetrate. The intertidal zone is the area where the ocean meets the land. The pelagic zone is the part of the open ocean comprising the water column.