Lecture 3

Question 1

You are an intrepid space explorer who has just landed on newly discovered planet X. While digging around in the dirt you come across single-celled creature that looks like a pineapple. You bring it into the lab to do some experiments.
First, you wonder whether it is a prokaryote or a eukaryote. Which of the following pieces of evidence would help answer your question
A) It’s single-celled, so it must be a prokaryote
 B) It’s single-celled, so it must be a eukaryote
 C) It responds to the environment, so it must be a prokaryote
D) It contains mitochondria, so it must be a eukaryote
E) It contains chloroplasts, so it must be a prokaryote

Answer 1

D) It contains mitochondria, so it must be a eukaryote

Question 2

You are an intrepid space explorer who has just landed on newly discovered planet X. While digging around in the dirt you come across single-celled creature that looks like a pineapple. You bring it into the lab to do some experiments.
You then jostle the table that the pineapple protist is on and suddenly spikes shoot out so it looks like an angry porcupine. Which of the following are NOT testable questions you might ask about the spines?
A) Are the spines used in courtship to impress mates?
 B) Are the spines used in defense againse predators?
 C) Are the spines used to grab onto the fur of passing animals?
D) Are the spines sharp?
 E) Are the spines used to hold onto the ground during storms?

Answer 2

D) Are the spines sharp?


Question 3

Prior to Mendel was the idea of what

Answer 3

blended inheritance

Question 4

what did Gregor Mendel do work on

Answer 4

Gregor Mendel— and his peas

Question 5

what was blended inheritance

Answer 5

Not only were children’s traits thought to be intermediate to those of their parents BUT their genetic material, whatever it was that they passed on the next generation was also thought to be a unique blend of both of their parents

Question 6

did blended inheritance work with natural selection

Answer 6

This made the idea of natural selection almost incomprehensible
there would be no way to pass on fitness if genetic material itself was altered by breeding

Question 7

what did mendel do with the peas

Answer 7

He then bred together different pure lines (e.g. smooth and dented seeds) and counted the number of offspring of each phenotype that resulted

Question 8

how did the pea experiment work

Answer 8

Start with pure breeds
RR genotype produces red phenotype
rr genotype produces white phenotype

If you cross a pure red (homozygous for R) and a pure white (homozygous for r) 
All offspring (F1 generation) are red and heterozygous

If you cross two F1 individuals
Red heterozygotes (Rr)
F2 generation is 3 red (1 RR, 2 Rr) and 1 white (rr)

Question 9

what is DNA

Answer 9

is your genetic material –directions

Question 10

what is gene

Answer 10

a sequence of DNA that contains information for making proteins

Question 11

what is protein

Answer 11

large molecules in your cells, they do most of the work in cells

Question 12

what are alleles

Answer 12

different versions of a gene, they have different DNA sequences. Sometimes these matter (and result in different proteins)
eye colours, hair colours, etc

Question 13

can there be multiple alleles of one gene

Answer 13

there could be lots of alleles for a single gene… but, if all allelic combinations produce the same phenotype, there will be no selection on that phenotype

Question 14

what are adaptions

Answer 14

Adaptations are traits that evolved through natural selection

Question 15

what do adaptation arise from

Answer 15

they arise from the phenotypic and genetic variation that is present
so, rather than stating from scratch to build the perfect solution, selection and adaptation work with what is there

Question 16

is selection intentional

Answer 16

Selection is not “intentional”

Question 17

what do adaptions depend on

Answer 17

They will depend on the environment :

the physical environment
the social environment

Question 18

what does it mean by Adaptations can result in generalists or specialists

Answer 18

individuals can be more flexible or have more “phenotypic plasticity ”
individuals can have traits that are more specialized for a particular niche

Question 19

what are the types of selection

Answer 19

Stabilizing selection
Directional selection
Disruptive or Diversifying Selection

Question 20

what is stabilizing selection

Answer 20

ideal weight (baby example) is in the middle, on either side natural selection will work against anything to the left or right

Question 21

what is Directional selection

Answer 21

a shift occurs when the environment around them forces them to adapt… so mice with white fur in snow would do great and ice with brown fur in snow would do terribly… wise versa when the mice are placed in a sand environment

Question 22

is phenotypic variation heritable

Answer 22

yes

Question 23

what is Disruptive or Diversifying Selection

Answer 23

the individuals in the middle would be lost, and the ones on the outside would be good (very rare for this to happen)