2.1 Species and Population

Question 1

Define Biotic Components

Answer 1

The living components of an ecosystem. Examples include animals, plants, fungi, etc.

Question 2

Define Abiotic Components

Answer 2

The non living components of an ecosystem. Examples include temperature, sunlight, water, etc.

Question 3

Define Species

Answer 3

A group of organisms that share common characteristics and can interbreed to produce fertile offspring. Examples include humans, leopards, pea plants, etc.

Question 4

Define Population

Answer 4

A group of organisms of the same species that live in the same area at the same time, and which are able to interbreed. Three factors affect population size: birth rate, death rate, and migration.

Question 5

Define Limiting Factor

Answer 5

A resource in limited supply that can affect the growth of a population.

Question 6

Define Carrying Capacity

Answer 6

The number of individuals in a population that the resources in the environment can support for an extended period.

Question 7

Define Population Dynamics

Answer 7

The study of the change in populations over time.

Question 8

Define Niche

Answer 8

The particular environment and “lifestyle” that a species has. It includes the place where the organism lives and breeds, its food and feeding method, activity patterns and interactions with other species.

Question 9

Define Fundamental Niche

Answer 9

The potential mode of existence of the species, given its adaptation.

Question 10

Define Realized Niche

Answer 10

The actual mode of existence of a species which results from its adaptation and competition from other species - that is, its actual lifestyle due to biotic interactions. A realized can only be the same size or smaller than the fundamental niche.

Question 11

Define Habitat

Answer 11

The environment in which a species usually lives. For example, the habitat of an orangutan is the rainforest of Borneo.

Question 12

Define Competition

Answer 12

Competition is when individuals compete for resources such as food and space.

Question 13

Define Intraspecific Competition

Answer 13

Population may compete with members of their own species.

Question 14

Define Interspecific Competition

Answer 14

Populations may compete with members of other species that use the same resources.

Question 15

Define Predation

Answer 15

Predation is an interaction between species in which one species, the predator kills and eats another, the prey.

Question 16

Define Herbivory

Answer 16

Herbivorous animals feed only on plants.

Question 17

Define Parasitism

Answer 17

Parasitism is a relationship on which one organism, the parasite, benefits from another, the host, which may suffer as a result of the parasite’s presence.

Question 18

Define Mutualism

Answer 18

Mutualism is a relationship between two organisms that gives benefit to both.

Question 19

Define the Lag Phase in a S or J Curve

Answer 19

When organisms become adapted to the conditions (medium).

Question 20

Define the Exponential Growth Phase in a S or J Curve

Answer 20

The period in which there are no limiting factors and the population can double in size in set time periods, which depend on the species.

Question 21

Define the Transition Phase in a S or J Curve

Answer 21

When a resource starts to becoming limiting and the rate of growth decreases.

Question 22

Define the Plateau Phase in a S or J Curve

Answer 22

When a population has reached stable, sustainable numbers, with births and immigration approximately equal to deaths and emigration.