Biodiversity

Question 1

Biodiversity

Answer 1

The diversity of the ecosystem, the number of different species and the genetic variation within the species

Question 2

What are the problems with separating an area into small fragments

Answer 2

Less choice of mates, could lead to interbreeding. Interbreeding depression leads to decrease in genetic variation. It might be difficult to find food. More easily exposed to danger outside area

Question 3

Advantages of zoos

Answer 3

Captive breeding and reintroduction. Education about the animals, can research the animals to find out about their behaviour. Can provide health care and fundraise for conservation projects in the wild

Question 4

Species

Answer 4

A group of organisms with similar morphology and physiology which can breed together to produce fertile offspring

Question 5

Niche

Answer 5

The role of an organism in an ecosystem

Question 6

Ecosystem

Answer 6

A relatively self contained community of organisms and the environment in which they live and interact

Question 7

Variation in ecosystem or habitat

Answer 7

Different organisms are adapted to different environments

Question 8

Variation in the number of species and their relative abundance

Answer 8

Species richness is the number of species in an ecosystem. Species diversity takes into account species richness and a measure of the evenness of abundance of different species. Ecosystems with high species diversity tend to be more stable and able to resist change

Question 9

Genetic variation within each species

Answer 9

Genetic diversity is the diversity of alleles within the genes in the genome of a single species. This can be assessed by finding out what proportion of genes have different alleles and how many alleles there are per gene. Genetic diversity provides populations with the ability to adapt to changes in biotic and abiotic factors

Question 10

Sampling

Answer 10

It is difficult to identify every single organism in an ecosystem, instead we take samples from areas and use this to make an estimate of the total numbers in an area. Sampling can be used to find the distribution of organisms and their abundance

Question 11

Quadrats

Answer 11

A quadrat is a large frame which marks off an area, you can identify the species in a quadrat and their abundance. Samples must be taken at random to avoid a bias, this can be done by marking off an area and using a random number generator to give you the coordinates on where to put down your quadrat. You need to decide a suitable size of quadrat and how many samples you will take

Question 12

Species frequency

Answer 12

The chance of a particular organism being found within a quadrat. You record whether a species is present and then divide that by the number of quadrats and then times by 100 to get the percentage

Question 13

Species density

Answer 13

How many individuals there are per unit area. The number of individuals you have counted is divided by the total area of all your quadrats.

Question 14

Percentage cover

Answer 14

You decide approximately what percentage of the area inside the quadrat is occupied by each species, can be used for grass where you cant count each individual plant

Question 15

Mark release recapture

Answer 15

A way of estimating the population size of mobile animals. As many individuals as possible are caught, they are marked in a way which will not affect their chance of survival. They are counted and left to mix with the rest of the population. When enough time for the mixing to take place has occured, another large sample is taken. The number of marked to unmarked individuals is counted. The proportion of marked to unmarked is then used to calculate the total number of the population. For example if in your second sample a tenth of the population were marked you would guess that you had originally captured a tenth of the population

Question 16

Systematic sampling

Answer 16

Used to show how the population changes across an area, for example as altitude changes

Question 17

Line transect

Answer 17

A line across one or more habitats. The organisms found at regular points along a line are noted. Transects are used to detect changes in community composition across a habitat

Question 18

Belt transect

Answer 18

The abundance of organisms within quadrats placed at regular points along the line are noted

Question 19

Simpsons index of biodiversity

Answer 19

Calculates a value indicating the level of biodiversity in the area, a value of 0 indicates low biodiversity and 1 represents a high level of biodiversity

Question 20

Pearsons correlation coefficient

Answer 20

Can be used to determine whether there is a linear correlation, with normally distributed data

Question 21

Spearmans rank correlation coefficient

Answer 21

Used when you are unsure about whether there is a correlation. Involves ranking the data recorded for each variable and assessing the difference between the ranks

Question 22

Taxonomic hierarchy order

Answer 22

Domain, kingdom, phylum, class, order, family and species

Question 23

Domain bacteria

Answer 23

Prokaryotic cells with no nucleus. DNA exists as circular chromosomes with no histone proteins associated with it. Has plasmids and 70s ribosomes. No membrane bound organelles. Cell wall is always present and made of peptidoglycan. Cell divides by binary fission not mitosis

Question 24

Domain archaea

Answer 24

No membrane bound organelles or nucleus. Has plasmids and 70s ribosomes. Cell divides by binary fission and not mitosis. Cell wall present but does not contain peptidoglycon

Question 25

Domain Eukarya

Answer 25

Cells have a nucleus and membrane bound organelle. DNA is arranged in linear chromosomes with histone proteins. Can be unicellular and multicellular. Has 80s ribosomes, chloroplasts, mitochondria and 70s ribosomes. Cell divides by mitosis. Many types of reproduction both asexual and sexual.

Question 26

Kingdom Protoctis

Answer 26

Eukaryote, exists as single celled or a group of similar cells. Some are animal like and have no cell wall, they are known as protozoa. Others are plant like cells with a cellulose cell wall and chloroplast, they are known as algae

Question 27

Kingdom Fungi

Answer 27

Eukaryote, they cant photosynthesise and have no chloroplasts. Heterotrophic nutrition they use organic compounds made by other organisms as their source of energy. Reproduce by means of spores. Either unicellular or made of long threads of hyphae. Cell walls made of chitin. Never have cilia or flagella.

Question 28

Kingdom plantae

Answer 28

Multicellular eukaryotes that have cells which differentiate to form tissues and organs. Some cells have chloroplasts and can photosynthesise (autotrophic nutrition). Cells have a large permanent vacuole. Cell wall made of cellulose

Question 29

Kingdom animalea

Answer 29

Multicellular eukaryotes with many different types of specialised cells that form tissues and organs. They don’t have chloroplasts and cant photosynthesise. Heterotrophic nutrition. Cell vacuole is small and temporary, no cell wall. Communication is via the nervous system. Cells sometimes have cilia or flagella

Question 30

Viruses

Answer 30

Viruses are not in a classification system as they have none of the features we traditionally use in classification. Some consider them to not be a living organism as they infect cells and use their biochemical system to copy their nucleic acid and make proteins. The energy for this process is provided by the respiration of the host cell. We classify viruses based on the type of nucleic acid (DNA or RNA0 and whether its single or double stranded

Question 31

Reasons why a plant may become endangered (2)

Answer 31

Habitat loss, human damage ie picking, climate change, soil erosion, use of herbicides, competition with other species and pollution

Question 32

Why is it important to conserve species (3)

Answer 32

To maintain biodiversity and genetic diversity. To ensure the stability of the ecosystem. Humans may have to use them for resources such as medicine. Aesthetic reasons, moral reasons