r/biology

Ich habe morgen Bio-BLF aber ich verstehe immer noch nicht den Chromosomensatz und die Anzahl an Chromatidchromosomen die die Meiose und Mitose während ihres Zyklus' haben. Egal wie viele Videos ich mir anschaue, es ist nie ausführlich genug, da bei den Chromosome nicht angegeben wird, ob es nun ein oder zwei Chromatide oder einfach das Chromosom selbst auf dem Karyogramm. Kann es mir jemand bitte in leicht erklären, ich verzweifle damit 😫

it’s really common were i work

english is’nt my first language

I was talking with a friend of mine over the biological evolution of humans and i had a question longing in me for me to ask WHAT EVOLUTIONARY THING MADE HUMAN THE MOST INTELLIGENT ORGANISMS EVER,is it brains or curiosity or what prompted to be like that and why isn't the dolphins or tigers gets the braniac power that we do???

Is it a evolution thingy or other factors contributing to this???

I ain't a biology student so explain to me in simple ways and pls no shaming since i come here for an answer..

So, it seems really common for people to get Appendicitis, which can get life threatening fast from what I've heard.

What purpose does the appendix have that makes it good to have despite it being a ticking time bomb in a lot of people?

Could be an animal, plant, fungus, sea creature, insect, microscopic organism, anything alive.

I am not a professional, I struggle to read scientific papers so it’s hard to get information on this. I will provide background on the death history of this infected flock.

My family purchased a small group of sheep nearly 11 years ago (2015). I quickly became the main carer of these sheep and this has remained the case since then.

In 2019 the ram who we purchased separately died suddenly of a mystery respiratory disease. The vet had done the “wheelbarrow test” to check for ovine pulmonary adenocarcinoma, but as no fluid came out it was decided not to be. However, this mystery “pneumonia” did not improve and he ended up dying, after death a huge amount of fluid left his lungs.

This left seven sheep, all had some relation in some way. 18 months later, the oldest ewe (let’s call her ewe A, aged 6-10 years) developed low body weight and nasal discharge. She was euthanised and it was obvious that it was OPA.

Next, ewe A’s daughter (let’s call her ewe A1, aged 6) developed the same symptoms suddenly and was also euthanised.

The half sister of ewe A1 (I will call her ewe B, also aged 6) showed no symptoms. However, one of her twin daughters from the deceased ram (I will call her ewe B3) developed symptoms and was also euthanised just two years later (2023). She was only 3 and a half years old, but was a small and weak lamb who was partially neglected by her mother, didn’t get colostrum and refused the bottle (her twin sister was huge).

This left four sheep. Ewe B, her first daughter (ewe B1), her following twins (ewes B2 and B3) and the castrated son of ewe A1.

The wether (castrated son of ewe A1) developed early symptoms, but died of another rare condition before he could worsen.

The three remaining ewes (ewe B and her two daughters) were showing no symptoms whatsoever. One died last year of unknown causes (ewe B2, aged 7), the other (ewe B1, aged 9) died this week of unknown causes.

I am left with ewe B. She shows zero symptoms of this disease, and neither did either of her daughters.

The thing is, this disease is supposed to begin the wasting process at 5-8 years old. This ewe is 11 and fat as can be. She has a good fleece, can run without coughing (a key symptom) and does not have nasal discharge.

Is it possible for a genetic line to be resistant to a retrovirus? My understanding was that resistance to this group of viruses is extremely rare.

I am in the south west of the UK, this disease is rarely seen around here. The vets have very little knowledge or experience with it. They didn’t even know that the “wheelbarrow test” guarantees euthanasia for an infected sheep (otherwise they will die slowly).

I became fascinated with this disease when I first found out they had it. I read every available online resource and even sat and watched hours of online presentations for farmers and vets in the Lake District (where it is common).

Having had these sheep for 11 years and dealt with this disease for 7, it feels strange knowing it will be over in a week or so when this ewe is euthanised (assuming she isn’t some kind of special medical anomaly!).

Can anyone explain how this might work in terms of the virus? How is it possible that she is not dying?

Interesting and fun article which ties biology to theories by Adam Smith and David Hume.

Can someone explain how the fluids in your inner ears affect balance? I get it’s something to do with the vestibular system and the fluids basically relaying messages to your body to maintain balance. But how do ear fluids necessarily affect a body’s arms, legs, feet, hands, torso, etc? Like why do people with weaker inner ears have trouble riding bicycles or learning to ice skate or roller skate?

I just graduated with my BS in biology and want to commemorate it somehow. I’ve got an appointment scheduled but have truly no idea what to get. I’m thinking of incorporating DNA, a flask, some flowers, something animal related (zoology concentration), maybe some atoms, viruses, a microscope… I have no idea. If you’ve got one I’d love to see it or just general ideas would be great! I’m either covering my forearm or doing the outer part of my thigh. I thought about winding dna up my thigh or arm and using it as a vine for flowers? I don’t know though. Thoughts?

I noticed that sometimes phenotypical diversity in Africa is underestimated sometimes because some people mainly focus on hair colour or eye colour. Plus, most people in the West are used to seeing West/Central African populations and their descendants (African-Americans, Afro-Caribbeans, Afro-Latinos, West/Central African immigrants in Europe) as the “default” for Black people.

However, while it’s known Sub-Saharan Africa has more genetic diversity than the rest of the world combined, it also has the highest phenotypical diversity. Even just focusing on one country like Ethiopia, you have populations with wide ranges in hair type (type 1 to type 4), skin colour (similar to Sicilian all the way to very dark brown black skin), a wide range of facial features and height, etc. Plus, epicanthic folds (which are usually attributed to East Asians) can be found in West African and Southern African populations. I don’t believe there is anywhere outside of Africa where native populations have the same range of hair types. You’ll also find the tallest ethnic groups and shortest ethnic groups in Africa. I also think you won’t find the same range of skin colours of native populations in a single country apart from India, but you will find such ranges in countries like Ethiopia and Somalia, etc.

Essentially, not only does Africa have a relatively high level of genetic diversity, it also has a relatively high level of phenotypical diversity, even just focusing on features people can see.