bio exam 1

Question 1

Dichotomous keys

Answer 1

an organized set pf couplets (two statements) that consist of mutually exclusive characteristics

Question 2

2 types of dichotomous keys

Answer 2

bracketed and indented

Question 3

reading a phylogenetic tree

Answer 3

Root: the common ancestor of all taxa
Node: represents a taxonomic unit or a branching point
Branch: defines the relationship between the taxa and changes in traits over time
Outgroup: a taxon that shares ancestral traits with the rest of the group, but is distinct
Polygamy: a node with more than two branches, often occurs when differences are not known

Question 4

monophyletic group (clade)

Answer 4

group of organisms descended from a common ancestor

Question 5

polyphyletic group

Answer 5

group of organisms descended from different common ancestors

Question 6

paraphyletic group

Answer 6

group of organisms descended from a common ancestor but does not include all descendants or the common ancestor

Question 7

homologous/synapomorphies

Answer 7

traits that are shared between organisms and are derived from a common ancestor

Question 8

symplesiomorphies

Answer 8

traits that are shared between all organisms in a given phylogenetic tree

Question 9

traits shared by all organisms

Answer 9

RNA, DNA, proteins, cell membranes

Question 10

evolution

Answer 10

a change in the genetic composition of a population over time

Question 11

population

Answer 11

a group of organisms of the same species that (1) occur in the same area and (2) interbreed or share a common gene pool

Question 12

gene pool

Answer 12

genes available in a population

Question 13

genes

Answer 13

sequences of DNA or RNA that code for a molecule

Question 14

alleles

Answer 14

genes that are responsible for variability
dominant (P) recessive (p)

Question 15

genotype

Answer 15

a genetic constitution for a specific organism

Question 16

phenotype

Answer 16

observable characteristic in an organisms due to genotype (eye color)

Question 17

genotype

Answer 17

genetic makeup

Question 18

homozygous

Answer 18

having the same allele on both chromosomes
RR (dominant) rr (recessive)

Question 19

heterozygous

Answer 19

having different alleles on either chromosomes
Rr (always codes for the dominant trait)

Question 20

Allelic Frequency

Answer 20

p + q = 1

Question 21

Genotypic Frequency

Answer 21

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

Question 22

prokaryotes

Answer 22

simple, single-celled organisms that lack a nucleus and other membrane-bound organelles

Question 23

Gram-negative

Answer 23

plasma membrane surrounded by thin peptidoglycan-poor cell wall and stain pink

Question 24

gram-postive

Answer 24

plasma membrane surrounded by peptidoglycan-rich cell wall and stain purple

Question 25

total magnification of compound microscope

Answer 25

40x (10 x 4) to 1000x ( 10 x 100)

Question 26

species

Answer 26

evolutionary independent monophyletic group for a given period of time

Question 27

diversity

Answer 27

number of different populations within an area of a researcher's interest

Question 28

species diversity

Answer 28

number of species and evenness of their abundances in a community

Question 29

species richness (S) Hmax: maximum possible H

Answer 29

Hmax= In(S) S= total number of different species

Question 30

species evenness (J) H' and Max are found, calculate evenness

Answer 30

J=H'/Hmax

Question 31

Shannon index (H') : combines S and J

Answer 31

H ́ = -Σ (pi ln pi)^s

Question 32

binary fission

Answer 32

clonal reproduction-daughter cells are genetically identical to each other and the parent cell

Question 33

transformation

Answer 33

some bacterial species can take up pieces of DNA from the environment

Question 34

conjugation

Answer 34

donor cell transfers DNA to recipient cell

Question 35

transduction

Answer 35

transfer of DNA between cell via bacteriophage

Question 36

infectious spread of a plasmid

Answer 36

plasmid may spread throughout the population