Exam 1: Lecture 4

Question 1

What chromosome is structurally similar between males and females?

Answer 1

the X chromosome the y is more complex and different

Question 2

What percentage of genes are the same across humans, and what percentage is different?

Answer 2

Around 0.5% of genes differ within humans, while 99.5% of genes are the same across individuals.

Question 3

How many chromosomes do gametes have?

Answer 3

Gametes contain half the number of chromosomes, specifically 23 unpaired chromosomes in each sperm or egg

Question 4

How many chromosome combinations are possible in gametes?

Answer 4

There are 2^23 possible combinations of chromosomes in gametes, leading to genetic diversity. This variation in gametes contributes to the genetic uniqueness of offspring

Question 5

How do cells determine their function?

Answer 5

all cells have the same genes but they specialize based on which genes are active

Question 6

what is the central dogma?

Answer 6

describes how DNA is transcribed into RNA, which is then translated into proteins.

Question 7

What performs most biological functions?

Answer 7

proteins and the variation in proteins is largely determined by which genes are expressed in specific cells

Question 8

How many chromosomes do chimps have?

Answer 8

48 chromosomes (24 pairs) this is due to how they are organized

Question 9

Why do humans have 46 chromosomes and not 48 like our great ape ancestors?

Answer 9

Some chromosomes in great apes have fused in humans, leading to the reduction from 48 to 46 chromosomes. Each end contains a telomere, and one in the middle of the chromosome indicating 2 were fused

Question 10

what is a telomere?

Answer 10

Each chromosome has telomeres at its ends, which protect the DNA from unraveling or fraying. this is common across species and serves to maintain DNA integrity

Question 11

what are alleles and how many do humans have?

Answer 11

different forms of a gene located at a particular locus on a chromosome. Humans typically have two alleles for each gene (one from each parent), but some loci may have multiple alleles, contributing to genetic variation. This variation is responsible for individual differences and population diversity.

Question 12

how much of our genes are shared with chimpanzees?

Answer 12

98.5% (4x as great as the differences between humans)

Question 13

What are 3 ways genetic diversity is introduced?

Answer 13

migration, sexual recombination, and gene flow from immigration

Question 14

Does genetic diversity continuously increase?

Answer 14

no

Question 15

does selection reduce or increase the variety of genes?

Answer 15

selection reduces the variety of genes

Question 16

How do alleles become more common?

Answer 16

Selection leads to the spread of beneficial genes within a population, making certain alleles more common.

Question 17

What is a fixed gene?

Answer 17

If an allele becomes present in all individuals in a population, it is no longer considered an allele but rather a fixed gene

Question 18

penetrance

Answer 18

how widely a particular allele is expressed across the population.

Question 19

what percentage of genes do humans share with rats?

Answer 19

90%

Question 20

Why are we so different from other species despite genetic overlap?

Answer 20

Even with such high genetic overlap, the expression of genes (which genes are turned on or off) plays a major role in the distinct characteristics of species (appearance, behavior, and physiological traits).

Question 21

Which has a greater role, nature or nurture?

Answer 21

they both have the same effect, 100%

Question 22

Is there more evidence that humans are biologically special or more against it?

Answer 22

more against it. The charles darwin theory that humans were not vastly different from other species this upset many people

Question 23

what makes humans “unique”? Name 7 things

Answer 23

1. bible
2. have a mind/soul independent of the brain
3. unique body
4. tool use
5. intellect
6. language

Question 24

How did Darwin view conflict with religious teachings?

Answer 24

in the context of creationism (humans created on a different day), it was one of the earliest arguments, Many religions also believe a soul survives biological death, although science has never proven that

Question 25

What other animals use tools and what do they use them for?

Answer 25

chimps use branches to collect termites, long-tailed macaques use stones to break open shells, whales use air bubbles to corral fish, sand wasps use fragments of mollusk shells to create nests, and polar bears use rocks to hunt, especially when hunting walruses, Caledonian crows use twigs to get insects; they save their tools to reuse and keep the ones that took more effort, showing they understand the value of effort invested.

Question 26

New Caledonian crows have high behavioral plasticity. What does that mean?

Answer 26

remarkable problem-solving skills

Question 27

how do monkeys make sex toys? what does this tell us about tools?

Answer 27

use stones as tools for sexual stimulation (this shows tools can have non-survival uses)

Question 28

What is the definition of a tool?

Answer 28

A tool is any object that helps manipulate the environment to achieve a goal, such as obtaining food.

Question 29

what is reflexive behavior?

Answer 29

Reflexive behavior, where actions are driven by instinct without conscious reflection (all nonhuman species are assumed to have this)

Question 30

What is control processing?

Answer 30

when a species is capable of conscious thought and control over their actions (it was assumed that only humans have this)

Question 31

Are nonhuman species smarter than we previously thought?

Answer 31

Yes, they show evidence of complex thought and problem-solving abilities, and we as humans may not be as intellectually advanced as one assumed. We may share more intellectual abilities than we originally thought

Question 32

is human behavior influenced by actions without awareness?

Answer 32

yes many actions become automatic and this develops early in life making it second nature ex: we walk without conscious thought

Question 33

Do our minds link experiences to certain objects or events?

Answer 33

Yes, e.g., a researcher ate a steak with sauce, so did his colleagues, but they didn't get sick. Years later, he still cant look at the sauce without his stomach turning; his brain linked the sauce to his sickness

Question 34

is there a mismatch between introspection and actual behavior?

Answer 34

yes ex: Tiger Woods was asked about his golf swing and his description didnt fully match his actions, Woods thought he was providing an accurate report but his muscle memory took over, showing a disconnect between introspection and actual behavior

Question 35

neural pathways

Answer 35

Information can be processed through neurons in the spinal cord without conscious awareness reaching the brain.

Question 36

learning seen in cats with spinal injuries

Answer 36

Cats with spinal injuries still exhibit learning behaviors, like withdrawing their foot in response to painful stimuli, even though the brain is not involved.

Question 37

What are Aplysia (sea slugs) and sea peligence (tiny wormlike creatures) useful for?

Answer 37

Aplysia has large neurons, making it easier to study how learning works in animals with simpler nervous systems. Sea Peligence: Despite its tiny brain with only 200 neurons, it can still learn, and that learning mechanisms is widespread across species

Question 38

Do species have different intellects?

Answer 38

Yes: each species has a different level of intellect, but it’s unclear if human intellect is vastly superior compared to other species.

Question 39

Why cant apes talk like us?

Answer 39

Apes have higher vocal cords compared to humans, which limits their ability to produce human-like speech. Despite this, they can learn simple signs in American Sign Language.

Question 40

the ape experiment

Answer 40

An experiment by a couple at the University of Nevada raised a chimpanzee alongside their child to observe language development. The child developed normally, but the chimpanzee began imitating sounds but didn’t develop full language.

Question 41

what sounds do chimps make to warn about predators or about food?

Answer 41

one sound is for predators that can climb trees; another is for those that cannot. also when food is found and what food

Question 42

Can chimps develop an understanding of syntax?

Answer 42

to some degree but not the level of complexity seen in humans

Question 43

What did the chimps Vicki, Washoe, Sara, and Nim Chimpsky learn?

Answer 43

Vicki—oral speech Washoe—American Sign Language Sara—magnetized plastic shapes Nim Chimpsky—symbols on keyboard

Question 44

Alex the parrot

Answer 44

Alex couldn’t fully speak like humans, he demonstrated the ability to use words and understand simple syntax. Alex’s researcher dedicated 30 years to teaching him language-like communication, and Alex could recognize objects, express feelings, and engage in simple conversations. Alex got his own obituary in the New York Times

Question 45

dogs and vocab learning (chaser)

Answer 45

Chaser, a boarder collie learned over a thousand object names and was able to identify them when asked. (this shows vocabulary learning

Question 46

a gene that produces our speech is also found in what other species?

Answer 46

Birds this suggested a genetic link in communication. Mice performed tasks with shapes with the same gene. This suggested a genetic link for learning and communication that is fundamentally similar across different animal species