Biology Higher 4 GCSE (only B4 and B5) Flashcards

Question

phenotype

Answer 1

the appearance of an organism

Answer 2

difference within a species

Answer 3

genetic- physical genetic material in an organism (dna) | environmental- the environment in which you live in

Answer 4

individuals that show characteristics that fall into distinct groups, such as blood groups

Answer 5

can have any value between minimum and maximum

Answer 6

``` usually produces clones examples: potato plants spider plants daffodils ```

Answer 7

requires 2 parents its offspring isn't identical since it uses 2 pair of genes it produces sex cells called gametes that fuse together in fertilisation.

Answer 8

advatages: if the parent can adapt well to an area, so can the offspring only one parent is needed- so its quicker to reproduce disadvantage: if there is a change to biotic or abiotic changes, it may destroy the entire species

Answer 9

advantage: variation in offspring leads to adaptations in a species disadvantage: reproduction requires 2 parents. It is much slower so fewer offspring are produced

Answer 10

diploid: 46 chromosomes haploid: 23 chromosomes

Answer 11

a fertilised egg cell

Answer 12

produces gametes | which are haploid cells (23)

Answer 13

1866- Gregor Mendel carried out an experiment on peas He noticed that characteristics were determined by hereditary units (now called genes) They are passed on from both parents and they are either dominant or recessive 1869- Nuclein discovered Friedrich Miescher discovered there is an acidic substance present in each nucleus (DNA) 1944- Genes can be transferred from one generation to another 1950- DNA base pairs found by Erwin Chargaff 1952- DNA crystals photographed by Maurice Wilkins and Rosalind Franklin 1953- Double helix structure James Watson and Francis Crick 1953- 2000 - Identified individual genes that code for genetically inherited disorders 2003- Human genome project completed- they discovered 24000 genes

Answer 14

a gradual change in species over time

Answer 15

1. Organisms show variation caused by a difference in their genes 2. The organisms with the characteristics that are best adapted will survive 3. genes from the successful will be passed down to their offspring 4. the process is then repeated many times

Answer 16

peppered moths- before the industrial revolution, moths were pale. then a mutation made them dark coloured, but they didn't survive because they couldn't camouflage against the light coloured trees after the industrial revolution, the trees were covered in soot so they became dark and the darker moths became more camouflaged against them, so they survived longer

Answer 17

1. the reptile dies 2. the flesh rots, leaving the skeleton covered in sand and soil before it is damaged 3. protected over millions of years, it becomes mineralised and turns to rock 4. eventually, the fossils emerge as the rocks move and erosion takes place

Answer 18

fossils of the simple organisms are generally much older compared to the more complex ones that are much younger plant fossils appear before animal ones- so animals clearly needed plants closely related organisms came from the same ancestor and this can be found by studying their anatomy

Answer 19

rapid change in species- as bacteria can replicate, scientists can study evolution in action and observe the changes extinction- species that are unable to adapt to environmental changes usually die out molecular comparison- scientists have began to compare the DNA and proteins of different species and the order of nucleic orders etc.

Answer 20

He joined a scientific expedition to the Galapogas Islands and he made his observation on finches. He saw that the beaks of the finches was entirely based on the types of food that they ate. At the same time that Charles Darwin was developing his theory, Alfred Russel Wallace gathered evidence for his theory, which was overall very similar to Darwin's so they did a joint report.

Answer 21

A universal system of naming species. The first name is the organism's genus. The second name is the organism's actual name

Answer 22

``` Kingdom Phylum Class Order Family Genus Species ```

Answer 23

looking for a common ancestor. the study of evolutionary links is known as phylogeny.

Answer 24

they group together organisms based off of their physical, observable characteristics.

Answer 25

a group of organisms that share the same genetic material and can breed to have fertile offspring

Answer 26

``` Identify gene for human tissue types isolate this gene insert this gene into the pig embryo replicate the gene check the cell for expression of the gene ```

Answer 27

an example of protozoa mosquitoes suck blood out of someone with malaria then pass it on

Answer 28

airways become swollen and restrict air flow. | muscles around bronchiols contract

Answer 29

people using CFCs, refrigeration | greenhouse gases increased