Inheritance, Variation and Evolution Flashcards

Question

What are dominant and recessive alleles? (Are they expressed, how are they represented) - IVE

Answer 1

Dominant - always expressed even if 1 allele is present, represented by a capital letter Recessive - only expresses if 2 of these alleles are present. Represented by a lower case letter

Answer 2

Homozygous - alleles are identical for each characteristic (AA/aa) Heterozygous - alleles are different for each characteristic (Aa)

Answer 3

Discover the parental genotypes. Split them into single alleles (DOM in CAPS, recess in lower) and add around edges of Punnett square. Combine in each box and calculate probabilities of each outcome

Answer 4

Males have XY chromosomes (heterozygous), females have XX chromosomes (homozygous)

Answer 5

Cystic fibrosis is a disorder which clogs the lungs with thick mucus which damages them Caused by recessive allele, meaning that only homozygous recessive alleles display the trait

Answer 6

Polydactyly is a condition causing someone to have extra fingers or toes. Caused by a dominant allele, meaning if you have the dominant allele, you expressed this trait

Answer 7

A faulty gene is identified, enzymes used to cut out normal allele from donor. These alleles are copied and inserted into the cells of a person with a mutation or faulty gene

Answer 8

Alleles may not be inserted into every target cell, may not be inserted into the right place in chromosomes

Answer 9

Pedigree analysis is the use of data on family history of genetic disorders to predict whether family members will inherit a disease

Answer 10

Mendel discovered that if you breed red flowered pea plants with white, all offspring had red flowers. Of the offspring that were bred, some had red flowers, some had white

Answer 11

We now know that one gene (RED) was dominant, whilst white was recessive

Answer 12

When he presented his work he didn’t fully understand it, his work was not published widely, couldn’t explain the science behind it

Answer 13

Variation is the process by which members of a species are not identical

Answer 14

Variation due to the combination of 23 chromosomes from each parent in fertilisation Blood group, skin colour, eye colour, sex

Answer 15

Characteristics that can be affected by diet, lifestyle, culture, accidents Scars, language and accent, weight

Answer 16

If a mutation is displayed in the phenotype and it is of benefit to the organism in a specific environment, then it can lead to the advancement of a species when passed on

Answer 17

A process where organisms that are better suited to an environment will survive and have more offspring and pass these traits on to offspring (Survival of the Fittest)

Answer 18

Charles Darwin came up with the Theory of Evolution. In 19th century, pollution made bark on trees become darker. Light coloured moths weren’t camouflaged and were eaten. Dark moths were and passed this trait onto offspring

Answer 19

Where humans breed plants/animals to produce desired characteristics Breeding Cows that produce lots of milk Breeding disease resistant wheat plants

Answer 20

+ves: new varieties can produce high yields of a product, animals can be bred that don’t cause harm (cows without horns) -ves: reduced genetic variation can lead to attack by diseases, can create physical problems unknowingly

Answer 21

A process which artificially transfers genetic information from one donor cell to another organism(s)

Answer 22

Identification of the desired trait, of which the gene responsible for this is cut out of the chromosome with an enzyme. The gene is transferred into a plasmid from a bacterial cell, and then into a bacterial cell where it can rapidly reproduce

Answer 23

Produce human insulin for type 1 diabetics Make herbicide resistant crops that can tolerate the herbicide Make 'golden rice' which helps improve human vitamin A production

Answer 24

+ve: faster and more efficient than selective breeding, improves crop yields or quality, makes herbicide resistance -ve: transfer of genes may cause widespread harm, not ethical to interfere with nature, can cause allergic reactions

Answer 25

A branch from a parent plant is cut off with lower leaves removed and the stem placed in compost. Plant hormones used to develop. After a few weeks a clone plant grows

Answer 26

Small pieces of plants are grown in vitro using agar jelly with hormones and nutrients. More expensive than taking cuttings but can preserve rare species or grow on a large scale

Answer 27

Sperm from a bull from high dairy yield herd artificially inseminates a cow. Zygotes develop into embryos and are harvested. These embryos are split into smaller embryos and transplanted into host mothers. IDENTICAL.

Answer 28

An unfertilised egg cell (without nucleus) is combined with the nucleus of a body cell to have full set of chromosomes. Given an electric shock to stimulate cell division. When the embryo is a ball of cells it is implanted into womb. Identical to body cell sheep

Answer 29

As an environment changes, individuals with certain traits are more suited to it and more likely to survive to pass these traits onto offspring. This leads to gradual evolution, as those without useful traits die out

Answer 30

A characteristic that is used more by an organism becomes enhanced and one that isn’t disappears. Any improved features are passed to offspring. An example is a giraffe's long neck, used to reach tall trees. This idea was WRONG

Answer 31

Individual organisms have traits more suited to an environment which means they are more likely to breed successfully. These traits are passed onto offspring, meaning a species gradually evolves

Answer 32

The theory challenged religious ideas that God made all animals and plants (creationism), insufficient evidence for Darwin's case, not proven for 50 years after publication

Answer 33

The idea of speciation, the formation of new and distinct species in evolution

Answer 34

The preserved remains of a dead organism from millions of years ago. Preserved in amber, peat bogs, tar, ice, rock

Answer 35

Fossils show the most basic, old organisms and more developed organisms, which show the evolution of species

Answer 36

Many soft-bodied forms of life have been destroyed be geological activity like volcanic eruptions or earthquakes

Answer 37

Random mutations occur in the genes of bacterial cells, which protect the cell from antibiotics. Bacteria without the mutation die from antibiotics, but the resistant strain can reproduce and evolve

Answer 38

MRSA Doctors should not inappropriately prescribe antibiotics where they aren’t needed, patients should always complete a full course of antibiotics to ensure all bacteria are killed

Answer 39

Extinction is when an entire species is wiped out | Caused by new diseases, new predators, new competitors, changes to an environment or a catastrophic geological event

Answer 40

Kingdom, Phylum, Class, Order, Family, Genus, Species | KIDS PREFER CANDY OVER FRESH GREEN SALAD

Answer 41

Genus + Species | Allows scientists to classify species accurately and individually

Answer 42

Archaea - primitive bacteria usually living in extreme environments Bacteria - true bacteria Eukaryota - protists, fungi, plants and animals