3.1- Classification

Question 1

define biodiversity

Answer 1

a measure of the variety of living organisms and their genetic differences

Question 2

define evolution

Answer 2

the process by which natural selection acts on variation to bring about adaptations and eventually speciation

Question 3

define taxonomy

Answer 3

the science of describing, classifying and naming living organisms

Question 4

define morphology

Answer 4

the study of form and structure of organisms.

Question 5

define analogous features

Answer 5

features that look similar or have a similar function, but are not from the same biological origin

Question 6

define homologous structure

Answer 6

structures that show common ancestry

Question 7

define species

Answer 7

a group of organisms with similar characteristics/morphology that interbreed to produce fertile offspring

Question 8

Describe the ecological species model and its limitations

Answer 8

Based on the ecological niche occupied by an organism. This is not robust because niche may vary and many species occupy more than one niche

Question 9

Explain mate recognition and its limitations

Answer 9

Based on unique Fertilisation systems such as mating behaviour. Limitation is many species mate or cross pollinate with other species producing fertile offspring.

Question 10

The classification system hierarchy consists of

Answer 10

Domain- Eukaryota, Bacteria and Archaea

Kingdom- 6 kingdoms- Archaebacteria, Eubacteria, Protista, Fungi, Plantae and Animalia

Phylum-
Class
Order
Family
Genus-group of species sharing similar characteristics
Species

Question 11

one limitation of using the textbook definition of species is that …

Answer 11

sexual dimorphism-different sexes from the same species may have different characteristics but they can still reproduce to make fertile offspring

Question 12

describe the 3 domain system

Answer 12

domains are archaea, Eubacteria and Eukaryotes

archaea consists of one kingdom called archaebacteria which is ancient bacteria

Bacteria domain contains one kingdom called Eubacteria which is known as true bacteria.

Eukaryotes domain is made up of 4 kingdoms
1. Protista
2. Fungi
3. Plantae
4. Animalia

Question 13

describe how a binominal name is written

Answer 13

in italics, first name starts with a capital letter and is the genus followed by lowercase letters showing the the species name

Question 14

define evolution

Answer 14

the process by which natural selection acts on variation to bring about adaptations and eventually speciation

Question 15

describe the genetic species model

Answer 15

a species model based on DNA proof

Question 16

describe the ecological species model

Answer 16

based on ecological niches (role in environment) occupied by an organism. One limitation is that many species overlap thus occupying more than one niche.

Question 17

describe the evolutionary species model

Answer 17

based on shared evolutionary relationship between species. Limitation includes the fact it is speculative for extinct or poorly documented species.

Question 18

describe the reproductive/biological species concept

Answer 18

organisms are grouped based on their ability to interbreed and produce fertile offspring. one limitation is that it is not applicable to asexual organisms or extinct species

Question 19

_______ _________ is the analysis of the genetic material of organisms to establish their evolutionary relationships

Answer 19

Molecular phylogeny is the analysis of the genetic material of organisms to establish their evolutionary relationships

Question 20

identify methods of distinguishing between species and determine evolutionary relationships

Answer 20

Gel Electrophoresis

Bioinformatics= the development of the software and computing tools needed to organise and analyse raw biological data, including the development of algorithms, mathematical models and statistical tests that help us make sense of the enormous quantities of data being generated

DNA sequencing= the process by which the base sequences of all or part of the genome of an organism are worked out.

DNA profiling= the process by which the non-coding areas of DNA are analysed to identify patterns

*** DNA sequencing leads to DNA profiling.

Question 21

describe the role of the scientific community

Answer 21

when research produces helpful results a scientific journal can be written. before being published it goes through peer review to check reliability. the paper needs to have enough detail so that other scientists can carry out the same investigation and see if it is valid

scientific conferences take place where scientists in similar fields come together to discuss ideas. opportunity to question validity and promote new research methods.

Question 22

describe the process of electrophoresis

Answer 22

make the agarose gel by dissolving powder in warm water. Place in mould along with comb and allow to harden

remove comb to leave 4 wells
fit the 2 pieces of electrode material to either end of the tank so that the ends dip into the channels

add 10cm3 of buffer solution into the tank using a 10cm3 syringe so that the gel is covered and ends of electrodes are wet

use a micro syringe to add one DNA sample into each well. DNA sinks to the bottom because it is denser than the buffer. DNA also contains loading dye as a visible marker to indicate progress throughout.

DNA is broken down into fragments by enzymes. (restriction endonucleases)

connect electrical leads to the correct terminal of the powerpack and switch it on.

positive electrode should be furthest from the wells.

watch until loading dye has moved across the gel towards the opposite end .

switch off power not allowing it to overrun and stain DNA to reveal the positions of DNA fragments as bands or spots.

Question 23

PCR?

Answer 23

Polymerase chin rection is used to make more copies of DNA before DNA profiling this is used especially in fossils since there is limited amount of DNA

Question 24

define endosymbiont

Answer 24

an organism that lives inside the cells or body of another organism

Question 25

define heterotophs

Answer 25

organisms that cannot make their own food and have to eat other organisms

Question 26

define autotrophs

Answer 26

organisms that can make their own food by photosynthesis or chemosynthesis

Question 27

define electrophoresis

Answer 27

a method of separating fragments of proteins or nucleic acids based on their electrical charge and size

Question 28

describe the FIVE kingdom classification system

Answer 28

Monera- containing archaea and Eubacteria
Protista- contains all single celled organisms
Fungi
Plantae
Animalia