Lecture 7, 8/9

Question 1

What are animal bodies distinguished by

Answer 1

• a tube within a tube

Question 2

What does a tube within a tube mean?

Answer 2

-inner tube = gut
-food enters in entrance and ingested food passes to the exit
- gut lies inside larger cylinder which houses all the other stuff

Question 3

about how many phyla in animal kingdom and what does it mean?

Answer 3

30
- own body plan that somehow varies the basic plan
- lifeforms sharing more of the pathway to LUCA = closer related and share more features

Question 4

What is the Cambrian explosion?

Answer 4

all the living animal phyla appear in the fossil record in a relatively short time span

• explosion of many new forms
• Cambrian = geological layer in which located

Question 5

Which life cycles are less varied plants or animals?

Answer 5

animals

Question 6

what kingdom is closest to animals?

Answer 6

Choanoflagellates
- fungi = not primitive plants

Question 7

how many vertebrate lineages are there

Answer 7

7

Question 8

how many lineages of fish are there?

Answer 8

6

Question 9

What are the phyla most closely related to chordates?

Answer 9

• hemichordate
• xenoturbellida
• echinodermata

Question 10

within the chordates who are humans closes relatives?

Answer 10

Tunicates
- evolution of skeleton is different (spinal cord and large brain = humans unique)

Question 11

What are the closest living twigs to hominids

Answer 11

2 chimpanzee species

Question 12

Did humans evolve from chimps?

Answer 12

No, we just share with chimps an ancestor who lived about 7 mya

Question 13

What does protostomes and deuterostomes mean?

Answer 13

protostomes = first mouth
deuterostomes = second mouth
means how does gut develop

Question 14

What are two characteristics of lophotrochozoans

Answer 14

• Lophophores function in suspension feeding in adults…
• Trochophore larvae swim and may feed

Question 15

All three lineages of chordates are defined by the presence of four features

Answer 15

1. Pharyngeal slits or pouches
2. Dorsal hollow nerve cord
3. Notochord
4. Muscular, post anal tail

Question 16

Who is the father of genetics

Answer 16

Gregor mendel

Question 17

What is selective breeding

Answer 17

• offspring resembled parents
• improve animal and plant varieties 19th century

Question 18

What was Mendel trying to do

Answer 18

improve taste, flavour, yield of peas

Question 19

what are genes and what do they do

Answer 19

• molecules
• code for mRNA molecules (transcription), which make proteins (translation), do work of building and running cell
• central dogma

Question 20

Where are genes located

Answer 20

on the chromosomes

Question 21

What is the cell cycle

Answer 21

• interval between cell divisions
• mostly growth and replication)

Question 22

what is mitosis

Answer 22

• replication division
• 2 cells identical to parent

Question 23

what is meiosis

Answer 23

• reduction division
• diploid -> haploid

Question 24

What is a locus

Answer 24

a particular place on a chromosome that any given gene is located in

Question 25

What are alleles

Answer 25

varieties of each gene

Question 26

What are homologous pairs?

Answer 26

a single chromosome pair one from dad and one from mom

Question 27

What is a tetrad

Answer 27

each homologue replicated to be 2 sister chromatids

Question 28

What are Mendel's laws and what does it mean

Answer 28

1. segregation 2. Independent Assortment - any of the possible combos of chromosomes from dad and mom is possible in any of the gametes

Question 29

What is phenotype

Answer 29

outward appearance

Question 30

what is genotype

Answer 30

actual genetic makeup

Question 31

what is epigenetic

Answer 31

heritable changes in gene function that do not involve changes in DNA sequence

Question 32

Is the expression of a trait always binomial?

Answer 32

no, some vary continuously depending on just which combo of alleles an individual has inherited

Question 33

What is the Hardy Weinberg equilibrium

Answer 33

any distribution of allele frequencies will quickly arrive at an equilibrium distribution

Question 34

What are allele frequencies

Answer 34

frequency (the proportion of the total present) of each allele type in the population/gene pool

Question 35

What is the importance of HWE

Answer 35

show that with a set of assumptions the allele frequency distribution quickly settles down to an equilibrium and shows no change over successive generations

Question 36

What are the assumptions of HWE/ what are the only ways in which allele frequencies change?

Answer 36

Gene flow = individuals move in or out of the population, carrying genes with them Genetic drift = the population is small enough that chance events can alter allele frequencies Non random mating = some mating combinations are somehow more likely than others Mutations = the spontaneous alteration of some alleles into others, the background rate is low enough that this is rarely a concern Natural selection = allele frequencies will change if some alleles contribute to better survival or more reproduction of the individuals that carry them than others…