bio 2 exam

Question 1

Biological species concept

Answer 1

members of the same species should be able to successfully mate with each other and produce fertile offspring
-Problems: It’s not practical to use since mating can be difficult to observe
-Does not apply to asexual species

Question 2

Ecological species concept

Answer 2

members of a species should have similar diets, habitats, etc… (ecological niches)
-Not very easy concept to utilize without a lot of research

Question 3

Phylogenetic species concept

Answer 3

members of a species should cluster together on the same branch of a phylogenetic tree
-Relatively easy and cheap to obtain and compare genetic sequences
-No assumptions about reproductive or ecological habits species do not have to have physical similarity

Question 4

Speciation

Answer 4

evolution of a new species
-New species accumulate differences old species from combination of natural selection and genetic drift changing allele frequencies

Question 5

Allopatry

Answer 5

each variety is its own range. Become species due to drift and local adaptation

Question 6

Sympatry

Answer 6

Many varieties in one range. Become species through adaptation to different aspects of the range

Question 7

Allopatric Speciation

Answer 7

Geographic barriers isolate populations of one species from each-other over time drift and selection make these different species

Question 8

Sympatric speciation

Answer 8

speciation occurs within the population with no geographic barrier
-Could be caused by mutations created differences in things like mating or feeding behaviors

Question 9

Adaptive radiation

Answer 9

A founding species can evolve into many new species if it is introduced into an environment where there are a lot of different resources to use or conditions to adapt to.

Question 10

Polyploidy

Answer 10

when an individual has more than 2 chromosomes per homologous set
-Can cause speciation when some individuals in a population have more than the normal number of chromosomes
-Can happen due to errors in meiosis

Question 11

Paedomophosis

Answer 11

when the juvenile stage of an organism becomes able to reproduce without completely transforming into the adult form.
- If these juveniles are different from adults in diet or habitat, they could become a new species

Question 12

Symbiogenesis

Answer 12

2 different organisms fuse their cells or tissues together to form a new species.

Question 13

Hox(Homeobox) Genes

Answer 13

control how structures develop along body segments
If these genes get moved around, duplicated, or get removed, they can cause major changes in body plan that can create new species.

Question 14

Mitochondrial Dna

Answer 14

Clonal DNA lineage that is useful for tracking ancestry since it’s sequence does not get scrambled up each generation and it accumulates mutations slowly
(only inherited from the mother.)

Question 15

Y chromosome DNA

Answer 15

Also useful for tracking ancestry: only inherited from father to son

Question 16

Multiregional hypothesis

Answer 16

older hypothesis that humans are not one species and something like H.erectus evolved separately in different regions into modern human racial groups.
-No support based on current evidence

Question 17

Bryophytes

Answer 17

mosses, liverworts, hornworts
-Most ancestral plants
-Life cycle is very similar to green algae
-Most are very small no tree forms (no vascular tissue)

Question 18

Pterophytes

Answer 18

Ferns, club mosses, horsetails
-These plants emphasize the sporophyte life stage over the gametophyte
-Otherwise, life cycle is similar to bryophytes with swimming sperm and wind-dispersed spores
-Have vascular tissue for sugar and water transport

Question 19

Gymosperm

Answer 19

cone-bearing plants

Question 20

Angiosperm

Answer 20

flowering plants
- seeds dispersed using fruit

Question 21

pollen

Answer 21

sperm contained in a hard capsule

Question 22

seed

Answer 22

contains dormant sporophyte embryo with energy store

Question 23

Anatomical Characteristics of Plants:

Answer 23

-Root-shoot body plan
-Look in notebook for drawing

Question 24

vascular tissue

Answer 24

ties together root and shoot systems
-In larger plants ( shrubs and trees) it forms the wood and bark that support and protect the plant

Question 25

Xylem function

Answer 25

-Pressure of water absorption in roots (root pressure)
-Adhesion and Cohesion of water molecules to each other and to xylem (capillary action)
-Evapotranspiration- water evaporates out through leaf pores (stomata)

Question 26

xylem

Answer 26

water transport from roots to leaves

Question 27

Phloem

Answer 27

Transport of sugars from leaves to other areas
Look in notebook for drawing

Question 28

Phloem function

Answer 28

Dissolved sugars made in photosynthesis from high concentration to low concentration through phloem (diffusion)

Question 29

gene

Answer 29

sequence of dna that codes for a phenoytipic trait

Question 30

allele

Answer 30

varients of a gene

Question 31

ex. of a gene

Answer 31

eye color

Question 32

ex. of a allele

Answer 32

is Brown (B) or blue (b)

Question 33

Homologous chromosome

Answer 33

Same gene but potentially different alleles

Question 34

Evolutionary change

Answer 34

changes in allele frequencies in a gene in a population overtime (population genetics)

Question 35

genetic drift

Answer 35

lowers change in allele frequencies through sampling error, or random change events where one allele is not more adaptive than another

Question 36

genetic bottleneck

Answer 36

drift in which most of original population dies and survivors randomly have different allele frequencies compared to original population

Question 37

founder effect

Answer 37

the type of drift when small genetically unrepresentative group founds a new isolated population

Question 38

Morphological species concept:

Answer 38

members of a species have similar physical forms
- problems: some species mimic the appearance of others, and some species are really variable in appearance

Question 39

Allele frequency

Answer 39

p+q=1

Question 40

Genotype frequency

Answer 40

p^2+2pq + q^2=1