Exam 2 Flashcards Preview

Bio 102 > Exam 2 > Flashcards

Flashcards in Exam 2 Deck (39):
0

What are the four requirements for Chemical Evolution?

Little to no oxygen
Source of energy
Chemical building blocks
Time

1

What is the prebiotic soup hypothesis?

Organic molecules formed near earths surface

2

What is the iron-sulfur world hypothesis?

Organic precursors formed at the cracks in the oceans floor

3

What is a protobiont?

The first cells-

4

What was most likely the first molecule of life?

RNA

5

What happens in the Precambrian era?

Life forms, we have the introduction of protobionts, bacteria and archea (prokaryotes) (3.5bya) , photosynthetic organism and oxygenation event (1.7-2.2 bya) and eukaryotes (2.1- 1.5 bya), Protista and fungi (1.0 bya) and animals (.75 bya)

6

When do the first fossils start appearing?

Precambrian- late Proterozoic

7

What are the two major events of the Paleozoic era?

Cambrian explosion- 542 mya
Permian extinction- 299 mya

8

What causes extinction?

Localized distribution
Over specialization
Interactions with other organisms
Habitat change / destruction
Natural events

9

What are the three most important mass extinctions?

Permian extinction- 255 mya

Triassic extinction- 205 mya

Cretaceous extinction- 65 mya

10

What era is the rise of the mammals?

The Cenozoic era

11

What groups evolved in the Cenozoic era?

Mammals
Flowering plants
Grasses
Birds

12

What is photorespiration?

When RuBp uses oxygen instead of CO2

13

What is mycelium?

The body of the fungi, made up of Hypha- small filaments

14

What are the 3 different cell wall structures in fungi?

Septate- all cells have cell walls
Septate (n+n) - cells have a cell wall with two nuclei in each
Aseptate- no cell walls

15

In fungi, which phase of life undergoes mitosis?

Haploid

16

In fungi, which phase of life undergoes meiosis?

The diploid

17

What are saprotrophs and what type of organism is one?

Organisms that obtain their nutrients from the dead, fungi are saprotrophs

18

What are the four types of fungi?

Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes

19

What are the characteristics of zygotmytotic fungi

Distinctive reproductive "zygospore" that ford around zygote

Examples- rhizopus--> bread mold
- pilobolus--> cow dung fungus

20

What are the characteristics of glomeromytotic fungi?

Form a obligate endo-mychorrhizal association with plant roots to help the plant absorb nutrients

21

What are the characteristics of ascomytotic fungi?

Reproductive cups called ascocarps made up of asci that produce spores.... Have a short stage of dikayrotic just before reproduction

22

What are the subgroups of ascomytotic fungi?

Conidiophores- molds like penicillium, aspergillus

Yeasts- Brewers and bread Yeast

23

What makes basidiomycetes unique?

Their reproductive structures are extremely large and come in 3 forms

- agaric
- stinkhorns
- shelf fungus

24

What kind of group is algae?

Polyphyletic- euglenoids, diatoms, grown and golden algae, archeplastids (red and green)

25

What events were primary endosymbiotic?

The addition of mitochondria and choroplasts

26

What kind of event was a secondary endosymbiosis?

A whole eukaryote takes in a eukaryotic algae

27

What are phaeophyta? What are their characteristics?

Brown algae- largest and most complex, multicellular, enveloped a red algae cell

28

What are coccolithophores?

Golden algae- unicellular with two flagella,protected by calcium carbonate

29

What are dinoflagellates?

Unicellular with two flagella, walls made of cellulose, causes red tides

30

What is the male producing part of a plant?

Antheridium

31

What is the female producing part of the plant?

Archegonium

32

What is the dominant stage of a bryophyte?

Gametophyte

33

What are tracheophytes?

Seedless vascular plants....club mosses, ferns

34

What are microphylls?

Outgrowths of stem tissue that developes into a singular vascular strand

35

What is the dominate stage of a tracheophyte?

Sporophyte

36

What is a gymnosperm?

Naked seed- seeded plant no flowers or fruits

37

What are male gametophytes called?

Microspores

38

What are female gametophytes called?

Megasporangium