Now that I’m past the 1,000 post mark, I thought I’d bring up an issue that has puzzled me during my time here on the SDMB:
Why do so many people seem to have such a poor understanding of biology?
I’m not talking about any sort of advanced science here, just the basics covered in Bio 101 or even high school biology. Things like natural selection, mutation, and recessive genes. This seems like pretty easy stuff to me (and I never studied biology beyond the required Intro Bio class my first year in college), yet again and again I come across people who just don’t seem to get it. They may know some of the vocabulary, but their understanding of the subject often seems at best simplistic and at worst superstitious.
I can’t remember ever even seeing a GD thread relating to biology that was free of these problems, and people I meet IRL are as bad if not worse. Just the other day one of my classmates wondered how apes could still exist if humans evolved from apes, while another claimed that the dolphin is the smartest kind of fish. These are students at an academically well-respected college. It can’t be that they’ve never studied science. So why don’t they get it? As my subject line asks, is biology really THAT hard? Why don’t more people get it? Is it poorly taught in most schools? Is there something about the subject that makes it difficult for many people to understand? Any thoughts on the matter would be greatly appreciated.
Why is chemistry THAT hard? Why is history THAT hard? Why is government THAT hard? I have met plenty of “educated” people who are equally as ignorant on these subjects as your friends are in biology. A few months ago I was asked why only one university was allowed to ellect the president and if I thought it shouldn’t be representatives from all the state run universities instead. Huh? University? You don’t mean the electoral col…
Anyway, my belief is that many subjects atrophy in peoples brains when not used. Yeah, they took bio 101 in high school, but they retained almost none of what they learned because they never use it. They took the class, passed it, but all they remember is “we disected a frog”. As they weren’t very interested in the subject to begin with, they did no further reading. Memory is imperfect and time started playing tricks with what they learned. After a few years, they lost the concepts completely. It happens to the best of us. Quick, how is a salt formed? What was the “Articles of Confederation”? Who are the senators from your state?
I prefer to believe the above rather than the possibly more likely scenario that people are just stupid.
Everything is hard if you don’t know it, and nothing is hard if you do know it. I agree with Beeblebrox. It’s not a matter of science being hard. It’s a matter of people being ignorant of science.
In my case, it was mostly a matter of not being able to get my brain to wrap around the subject- which was a combination of “this is too damned tough” and “this is too damned boring.”
My opinion is that people have individual strengths and weaknesses when it comes to various topics, which may be simply how much the topic interests them, or it may just be how well their thought processes can handle the necessities of the topic.
For example- I graduated from college with a history degree and a 3.something in my history classes. I also never passed a single biology class except by the skin of my teeth. Both subjects involved a lot of memorization (places, names, and dates for History; things, functions, and whatsits for biology) but because I felt a connection and an interest to the History subjects, I was better able to remember what I was taught.
Still, that doesn’t explain why I’m terrible with languages. I love the concept of languages, I love the idea of being able to speak other languages, and I’ve failed miserably at trying to learn French, Italian, and Russian. So that leads me to believe that brain function has something to do with it.
I think it’s due to people not using it once they get past their required “Bio 101” course. Also, during their time in said course, they know they won’t be using it in their “real” job, so they do just enough to get by. There is a big difference between studying to learn the material, and studying to pass a test.
Of course, some of the things mentioned are just a matter of willful ignorance/apathy.
~~I majored in biology because it’s something that I like…
That’s the only reason it wasn’t hard for me… I don’t think
it’s poorly taught… I think most people think of it as yuck…
Even still when I’m talking to another bio person I’ll use
slang that is frowned on by the bioeducated…
I know better; Sometimes I just don’t care… No journal
entry here…
But I was the weird one who also liked organic chemistry…
I’m willing to answer any question anybody has about biology. Maybe a GQ “Ask the Geneticist” thread if I have the time and need the ego boost.
In my experience, most people that I know have had relatively poor science education in high school. The biologists are the ones to overcome that. Even my high school biology teacher, who was one of the better ones at the school, IMHO sucked all the fun out of the science. My chemistry teacher was famously bad and it took me until sophomore year of college to actually appreciate it. And I went to one of the top high schools in my city.
Biology can be taught in an interactive and fun setting. Labs can be fun and not tedious. Abstract concepts can usually be applied to real-world situations: genetics to familial traits like color blindness and baldness and eye color, metabolism to dieting, evolution to antibiotic resistance and disease for example. That is how I try to teach it when I tutor and lecture at schools. We are surrounded by biology and it is one of the easier subjects with which to answer the famous high school question “When will I ever use this?”
Don’t forget that, especially in your example of biology (natural selection, humans evolved from other life forms, etc.), prejudice and bias play large parts in what people “choose” to understand.
I live in Alabama. My bio teacher did NOT cover any evolutionary theories. The only reason I knew what natural selection was is because I’d been reading the encyclopedia since age 5.
We also glossed over mutation. I really don’t know how or why something mutates, I just know sometimes it does.
We went over heredity pretty thoroughly, so I understand that fine. Cell makeup/division as well, and sickness and how it works, blah blah blah.
I don’t know taxonomy. We had just barely gotten into it when school was over. I’m not sure what we wasted the year on. Cells and heredity, I think. Cells the first semester, heredity the second.
My Alabama education is one of the primary reasons I’m not a science major–my science teachers sucked. It’s kind of sad, because I think I could’ve understood and enjoyed chemistry and physics, but the teaching was so horrific and dismal that I’d probably fail an Intro course on either subject, so I’ll just stick to my psychology and theatre studies, because those two high school teachers were FABULOUS.
I have actually been thinking of doing this for a while, but haven’t had the time. I was planning to ask you to help me with it, too. Great minds think alike, eh?
It’s my understanding that the meiosis process involves the following steps:[ul][li]The chromosomes on either side of each chromosome-pair within the nucleus swap some of their genes.[/li][li]The cell undergoes normal mitosis with these gene-swapped chromosomes.[/li][li]Each of the two daughter cells undergo an abbreviated form of mitosis in which they divide but don’t replicate their chromosomes. One chromosome from each chromosome-pair goes to one of the granddaughter cells, and the other chromosome of the pair goes to the other granddaughter cell that was spawned off of the same daughter cell; thus, the granddaughter cells are haploid gametes.[/ul][/li]It’s also my understanding that an ovulated, unfertilized oocyte (egg cell) still has a full set of chromosome-pairs. This means it hasn’t undergone the full meiosis process. My question is, has the oocyte already undergone step 1 of the meiosis process as outlined above? I.e. have its chromosome-pairs swapped genes yet?
I ask because I’ve recently heard about a cloning strategy whereby they take an unfertilized oocyte and make it start dividing into a blastocyst as though it were a zygote. If its chromosome-pairs have swapped genes before this happens, then that means the genome isn’t identical to the other cells in the woman’s body and the embryo won’t be a “true” clone.
Yes, but before this happens, DNA replication. Crossing over occurs in a structure called a tetrad, where four homologous chromatids line up.
It isn’t normal mitosis, the cell undergoes meiosis I. Both result in diploid daughter cells, but in mitosis the sister chormatids separate at the centromere. In meiosis I the centromere stays intact and the homologous sister chromatids that make up the tetrad separate. So itstead of getting one of each chromosome you get two of one half of the chromosomes (plus some crossing over).
This is called meiosis II, and yes it is very similar to mitosis, but it lacks DNA replication beforehand. DNA replication really can’t occur because all the chromosomes are locked up in the sister chromatid structure, which is the usual result of DNA replication. In this step the chromatids break apart at the the centromere, one half goes to one daughter cell the other half to the other daughter cell.
No. Once the cell has ovulated, it has completed meiosis and is haploid.
Yes, because meiosis has been completed.
I have heard of this, but I don’t know which cell they are using. Women form primary oocytes while they are still embryos. These oocytes arrest their development at Prophase I, after DNA replication, but before crossing over occurs. Meiosis resumes during puberty, when ovulation starts. Maybe they take the primary oocyte and force it to undergo normal mitosis, where crossing over would not occur, or maybe they take a different cell. The news reports arent clear.
It is best to think of a normal human cell has having one complement of the genome (a full genome set) and two copies of each gene on chromosomes. Two copies of each gene mean that the cell is diploid.
In meiosis and mitosis, a cell divides its DNA, making for 2 complements of DNA, now stored on sister chromatids. Meiosis I is a halving of the diploid number and completely unlike what happens in mitosis – the chromosomes separate, but the sister chromatids remain together. This leaves a haploid cell with still 2 complements of the genome.
This happens in sperm and eggs every day. IIRC only eggs in a narrow window are ovulated and the rest are degraded (atresia). Generally (depending on organism, I take it you are talking about most mammals including humans), the egg is halted in the middle of meiosis II (second metaphase) and does not progress further until fertilization. Sperm continue meiosis and mature constantly. Meiosis II is similar to mitosis, in that sister chromatids separate to halve the two complements, leaving gametes with one complement and one copy of each gene.
Upon fertilization, a number of events take place. The physical penetration of the sperm causes a cascade of events by a calcium wave. One of these is for the completion of meiosis II and formation of two female pronuclei, with ejection of one into a nurse cell. A few hours later, after the sperm pronucleus reforms, the male and female pronucleus fuse to make a complete genetic organism. Interestingly, in mammals, a diploid nucleus is never formed in the one-cell stage – the cell immediately proceeds into mitosis. Thus, the first true diploid cells in mammals are at the two-cell stage.
is half-and-half. The cell is haploid but not completed meiosis.
and tracer:
I have heard some stuff about this in the popular press but since it isn’t my field I really don’t have that much to clarify. I will just say that in doing this there are some major obvious hurdles to overcome. The first is of course simulating fertilization without a sperm, and completing cell division with a haploid number. Generally cells will get halted in the cell cycle if they do not have the correct chromosome number and won’t grow.
Second, that being said, there are some disorders where a parthenogenetic (only mother-derived) event occurs. These are called hydatidiform moles, which are usually derived from either gamete formation problems or errors in signalling, and the cells do develop like blastocysts. The problem is that they don’t differentiate, which is thought to be due to a pretty complicated genetic mechanism called imprinting. See, it matters for some genes whether you inherit the copy from your father or your mother. Some genes are activated in the maternal germline and repressed in the paternal germline and vice versa. This pattern is maintained throughout post-fertilization and throughout life in most cells. In these genes, only one of the two copies is active (either the paternal or maternal copies) and big problems can arise from having two or no active copies.
Don’t know how they overcame these. If you find a reference, please pass it along. Fanks.
Simulating fertilization without sperm is accomplished in different ways in different species: in sheep you use a combination of chemicals called ionomycin and 6-DMAP, in pigs you use an electrical pulse. Both methods serve to stimulate the intracellular calcium spike that is normally caused by the sperm at fertilization.
You can get cell division in embryos up to a certain point with haploid numbers. I’m not familiar with the technique y’all described as being considered a true cloning technique. When we activate oocytes in our lab, it is to create parthenotes, not clones, and it is with the knowledge that these parthenotes will not continue to develop past a certain point.
You can also get (a much greater degree of) development in embryos that have polyploidy. This happens often in in vitro produced pigs, because there is a big problem with polyspermy in this species. A paper recently came out which showed that these embryos can develop past the blastocyst stage, and in fact produce live piglets. Some of the piglets had normal chromosome numbers at birth, indicating that the problem has some ability to fix itself in utero, and others were born with abnormal chromosome numbers. I’ll have to wait until Monday to give you a cite, sorry. The paper’s on my desk at work.
Actually, parthenogenotes can be either maternally or paternally derived. The maternally derived are called gynogenetic and the paternally derived are androgenetic. For some reason I was thinking it was the paternally derived that form hydatidiform moles, but that’s something else I’d have to look up at work on Monday. Either way, one type forms an embryo that’s mostly embryonic tissue with very little placental development, and the other (the hydatidiform moles) forms huge amounts of extra-embryonic tissue.
Sorry about all the unsolicited detail, but this stuff is so cool!
Like I say, give me until monday and I can come up with some articles.
In response to the OP, I agree that it’s just a matter of what you use all the time being the easiest to understand.
For example, (and I canNOT believe that I’m actually going to admit this on this bulletin board. I must be more masochistic than I thought), while I have a world of biological knowledge, I truly suck at geography. Now, I like to think that I am not a moron, but because of a couple of moves in junior high and high school, I completely missed taking geography. And since I don’t really care too much about geography, I didn’t bother to take it in college. This was clearly a mistake, as was brought home to me when I recently found out that New Mexico is a state and not a city. Yipes.
I don’t know that it’s necessarily hard–I think that sometimes people’s misunderstanding of things like natural selection and mutation are due to the fact that these concepts are often applied inappropriately in popular culture (books, media, etc.)
Fortunately, I come from a family of biologists and whenever I’m confused, I can just ask a relative. I would venture a guess (already stated in this thread) that people simply have different strengths and weaknesses. For instance, though I may know a little more about bio than the average person, I’m completely at sea when it comes to basic physics.
I think you have a good point. It’s all about relative weaknesses, because few people are good at everything. For some reason some of my friends with science degrees found it oddly upsetting, when we were in college, that I understood what they were telling me, even though I was majoring in English. I think they found it somewhat threatening, because they were not as good at English. However, unlike them, I have a very poor understanding of math. I barely passed my math classes from 11th grade on, and I can’t even multiply two digit numbers in my head and get the correct answers consistently…it just don’t “click” at all for me. Perhaps when it comes to biology, your friends are showing their Achilles heels, too.
I agree with Beeblebrox. It’s not a matter of science being hard. It’s a matter of people being ignorant of science.