Unit 1 test Flashcards
How many genetically different kinds of gametes can an individual with the following geneotype make?
AaBbCcDdEeFf
2^6=64
why do we use the formula 2^n to find how many different kinds of gametes they make?
because there are only 2 alleles for each gene
How do you find the probability of offspring with the following genotype: AABBCCddEE?
Parents: AABbCcddEE x AABbCcddEE
You do each separate genotype’s punett square and multiply all of the possible outcomes for that specific genotype
I.e: AA x AA
A. A
A AA. AA
A AA. AA
4/4 = 1 so 1 x other outcomes for (BBxCCxddxEE)
what is the chi square test?
find the probability that the difference between the observed and expected is due to chance alone
what is the chi square formula?
x^2 = sum[(obs.-exp.)^2 /exp.]
the bigger the chi square value, the…
bigger the deviation from the exp. value
degrees of freedom are…
the number of alternate outcomes compared to the exp.
what is the formual for degrees of freedom?
N-1
(N=number of outcomes)
what is the alpha-value in the chi square test?
threshold for rejecting the null hypothesis
E.g: alpha=0.05 means there is a 5% chance we reject our null hypothesis that is actually true
anything less than 0.05 means we…
consider the results significant
If the value is lower, we reject the null hypothesis
what is the p-value?
it’s what you look at on the critical values table for the chi square value once calculated.
what can you say about the conclusion of inheritance when the p-value you found on the critical value chart from your calculated chi square value is less than 0.005?
it’s less than** 0.05** so this means the genes show significant deviation from our expected results…
We reject our null hypothesis since something else is going on
where does your expected value come from in the chi square value?
when you perform a punett square from the genotypes you are given
Ex: Tt x tt
n (population) = 200
Punett square:
T. t
t Tt. tt
t tt. tt
Tt=2/4
tt=2/4
1:1 ratio meaning
half of the pop. will be Tt and the other half will be tt
what do we conclude if our p-value is between 0.1<p<0.5?
We accept the hypothesis
Not lower than 0.05
what ratio does a dihybrid cross produce?
9:3:3:1
what is the degree of freedom for the cross between BbVv x (bb v v)?
4-1=3
if the population is 2,300 (n) and the cross is between BbVv x (bbv v),
what is the expected value for BbVv?
Punett square;
BV Bv bV bv
bv BbVv Bbvv bbVv bbvv
BbVv= 1/4
so…
2300/4= 575 is the expected value
what is a dichotomous key?
key characteristrics that classify animals
what are the key characteristics to look at in using the dichotomous key? (5)
-Type of symmetry
-Presence of cephalization
-presence of segmentation
-presence of appendages
-type of skeleton
What is taxanomy?
biological field of classifying and naming all forms of life
what are the 3 domains?
-bacteria
-archaea
-eukarya
what are the 3 types of symmetry?
-asymmetry
-radial symmetry
-bilateral symmetry
what does radial symmetry mean?
body is shaped like a pie or barrel and can be sliced like a pizza or pie
what does bilateral symmetry mean?
body is symmetry meaning if split the organism in 2, it will be symmetrical on both halves
what is an ex of radial symmetry?
starfish
what is an ex of bilateral symmetry?
a fly
practice on Tobie the terms of bilateral symmetry
what is segmentation?
division of animal body plans into a series of repetitive segments
what is a type of segmentation?
metamerism which is linear series of body segements fundamnetally similar in structure
what are the advantages of segmentation? (2)
-compartmentalization
-specialization with respect to bodily regions
what is an arthropod?
typical insect
what does an insect have? 3 compartmentalizations…
-head
-thorax
-abdomen
what is cephalization?
evolutionary trend toward the concentration of sensory equipment at the anterior end of the body (the head)
what did cephalization evolve in bilaterally symmetrical animals?
nervous system
does cephalization occur in all organisms?
no, only bilaterally symmetrical animals
what are appendages?
external body parts that protrude from an organism’s body
what are homologies of the forlimb in 6 vertebrates? (5)
-humerus
-radius
-ulna
-carpals
-metacarpals
-phalanges
what does endoskeleton mean?
internal skeleton
what is phylogenetics?
estimating evolutionary past
what is phylogeny?
based on comparing DNA or protein sequences describing speciation events within a group of organisms
what is a clade?
group of organisms that share a common ancestor
what is a taxon?
any grouping of 1 or more populations/organisms
what does a node signify?
speciation event from last **common ancestor **
What does homology mean?
similarities between features of structure and function due to common descent
what does convergence/analogy mean?
similarities between feature of structure and function due to **common environment **but not common descent
what is an example of homologous traits?
pig insulin and human insulin
what is an example of analogous trait?
wings of a bat and wings of a wasp
