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Flashcards in Module 4 Deck (57)
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1

What are the 5 kingdoms?

Prokaryotae, protoctista, fungi, Animalia, plantae

2

General features of prokaryote

unicellular, no nucleus or membrane bound organelles
(e.g. bacteria such as E.coli)

3

General features of protoctista

mainly unicellular, nucleus and membrane organelles, some have chloroplasts
(e.g. Amoeba)

4

General features of fungi

uni/multicellular, nucleus and other membrane bound organelles, cell wall of chitin, saprophytic feeders

5

General features of plantae

multicellular, nucleus and other membrane bound organelles, contain chlorophyll, autotrophic feeders

6

General features of Animalia

multicellular, nucleus and other membrane bound organelles, heterotrophic feeders

7

What are the 3 domains

Eukarya (80s ribosomes)
Archaea (70s ribosomes)
Bacteria (70 ribosomes)

8

What is prokaryotae split into in the six-kingdom system

Archaebacteria (ancient bacteria that live in extreme environments)
Eubacteria (bacteria found in all environments)

9

What evidence is there for evolution?

Palaeontology, Comparative anatomy and comparative biochemistry.

10

How is palaeontology evidence for evolution?

Complex fossils found in recent rocks
Sequence in which organisms are found match their ecological links
Studying anatomy can show how closely related organisms are

11

How is comparative anatomy evidence for evolution?

Homologous structures (structures that appear superficially different but have the same underlying structure) provide evidence for divergent evolution (closely related species diversify to adapt to new habitats)

12

How is comparative biochemistry evidence for evolution

Similarities and differences in cytochrome c and ribosomal RNA

13

What are genetic causes of variation?

Genes have different alleles
Mutations
Meiosis (crossing over and independent assortment)
Sexual reproduction
Chance

14

What are environmental causes of variation?

Sunlight, food, shelter, scars

15

What are environmental and genetic causes for variation?

Height= parents may be tall but diet also affects growth
Skin colour=genetics and how much melatonin skin contains

16

What are anatomical adaptations?

physical features

17

What are behavioural adaptations?

the way an organism acts

18

What are physiological adaptations?

processes that take place inside an organism

19

What do analogous structures provide evidence for?

Convergent evolution (unrelated species begin to share similar traits)

Analogous structures=species have adapted to perform the same function but different genetic origin

20

What is species richness?

the number of different species living in a particular area

21

What is species evenness?

a comparison of the number of individuals of each species living in a community

22

What is opportunistic sampling?

Uses organisms that are conveniently available

23

What is stratified sampling?

populations divide into strata based on a particular characteristic (e.g..male and female)

24

What is systematic sampling?

different areas within a habitat are identified, which are sampled seperately.

25

Why is sampling never entirely representative?

Sampling bias and chance

26

Factors that increase genetic biodiversity

Mutations
Gene flow (interbreeding between different populations)

27

Factors that decrease genetic biodiversity

Selective breeding (artificial selection)
Captive breeding
Natural selection
Genetic bottlenecks (a few individuals within a population survive event/change)
The founder effect (where a small number of individuals geographically isolate themselves)
Genetic drift (when a particular all disappears from a population)

28

How can human interfere with biodiversity?

Deforestation, agriculture, climate change

29

Aesthetic reasons for maintaining biodiversity

Presence of plants and animals, inspiration for writer and musicians, reduce stress

30

Economic reasons for maintaining biodiversity

Soil erosion and desertification can reduce crop growth, species with potential economic importance may become extinct (medicinal and chemical uses) ecotourism,

31

Ecological reasons for maintaining biodiversity

Disrupt food chains, when a keystone species is removed the habitat is drastically changed

32

What is the IUCN?

Publishes the red list, detailing threatened animals

33

What is CITES?

Regulates international trade

34

What is the Rio Convention?

Maintains biodiversity

35

What is the Countryside stewardship scheme?

Sustains the beauty and diversity of the landscape, improves biodiversity

36

What is ring rot?

A bacterial disease in potatoes and tomatoes. No cure

37

What is tobacco mosaic virus?

A virus that infects tobacco plants. No cure

38

What is potato blight?

Caused by a fungus-like protoctista. The hyphae penetrate host cells. No cure

39

What is black Sigatoka?

A diseased caused by fungi that affect bananas. Fungicide can control the spread but no cure

40

What is TB?

A bacterial disease that destroys lung tissue and suppresses the immune system. Curable

41

What is bacterial meningitis?

A bacterial infection of the brain. Curable

42

What is HIV/AIDS?

Caused by a virus suppressing the immune system. Transmitted by bodily fluids

43

What is influenza?

Viral infection of the ciliated epithelial cells in the gaseous exchange system.

44

Physical plant defences

Callose deposited between cell walls and cell membrane, sieve plates in the phloem and in the plasmodesmata

45

Chemical plant defences

Insect repellant (citronella)
Insecticides (caffeine)
Antibacterial compounds (phenols)
Antifungal compounds (chitinases)
Anti-oomyctes (glucanases)
General toxins (cyanide)

46

Non specific animal defences to keep pathogens out

Skin, mucous membranes, lysozyme in tears and urine
Blood clotting
-thromboplastin results in the formation of a blood clot
-serotonin makes smooth muscle in blood vessels contact, reducing blood supply
Inflammatory response
-histamines raise the temp preventing pathogens reproducing and make blood vessels more leaky so blood plasma is forced out, tissue fluid causes swelling
-cytokines attract phagocytes for phagocytosis

47

Non specific animal defences to get rid of pathogens

Phagosome-phagolysosome-enzymes digest and destroy pathogen-MHC forms-MHC moves pathogen antigens to the surface membrane- forms APC

Cytokines- cell signalling molecules, informing other phagocytes that the body is under attack
Opsonins-tag pathogens so they can easily be recognised by phagocytes

48

How do antibodies defend the body?

Act as agglutinins causing pathogens to clump together, easier for phagocytes to engulf
Act as anti-toxin, binding to toxins produced by pathogens making them harmless

49

What do T helper cells do?

produce interleukins stimulating B cells, which increase antibody production

50

What do T killer cells do?

produce perforin which kill pathogens

51

What do T memory cells do?

have an immunological memory

52

What do T regulator cells do?

suppress the immune system, preventing an autoimmune response

53

What do plasma cells do?

produce antibodies

54

What do B effector cells do?

divide to form plasma cell clones

55

What do B memory cells do?

have an immunological memory

56

What is cell mediated immunity?

When cells change (cancer)
Macrophages engulf and digest phagocytes forming an APC
Complementary T helper cells produce interleukins which stimulate more B and T cells to divide

57

What is humoral immunity?

When foreign pathogens are recognised
-Activated T helper cells bind to B cell APC (clonal selection)
-Interleukins are produced, activating B cells
-Activated B cells divide producing clones of B memory and plasma cells (clonal expansion)
-Plasma cells produce antibodies which bind to the antigens on the surface of the pathogen, disabling them or act as oppsinins/agglutinins (primary)
-If the body is infected again B cells divide rapidly to form plasma cells, which destroy the pathogen (secondary)