سلول های پروکاریوتی دارای هسته ی واقعی نیستند یعنی ماده ژنتیکی آن ها توسط غشای هسته ای احاطه نشده است.موجودات تک سلولی مانند باکتری ها دارای این نوع سلول هستند.
اندامک ها بخش های تخصص یافته ای هستند که هر کدام وظایف ویژه ای به عهده دارند.
نخست به اندامک هسته سلول می پردازیم . در هسته دی ان ا یا همان ماده ژنتیکی سلول وجود دارد که وظایف سلول و چگونگی انجام این وظایف را تعیین می کند .
#nucleos#DNA#هسته ی سلول #cellstructure#cellbiology
0 67 hours ago
Happy Monday 💕
Despite being nice and sunny it’s actually really cold today so I’m pretty glad my lab coat is providing me with an extra layer ❄️🥼!
سلول ها کوچکترین واحد زنده سازنده ی موجودات زنده هستند.تمام سلول ها بدون در نظر گرفتن نوعشان معمولا دارای سه بخش غشای سلولی و سیتوپلاسم و دی ان ا هستند.غشای سلولی درون سلول را از محیط اطراف سلول جدا می کند.سیتوپلاسم سیال ژله مانند است. دی ان ا همان ماده ژنتیکی سلول است.سلول ها دو نوع عمده دارند.سلول های یوکاریوتی و سلول های پروکاریوتی.سلول های یوکاریوتی دارای اندامک های مختلف از جمله هسته سلول هستند.سلول های یوکاریوتی پیچیده ترین و متنوع ترین نوع سلول ها مانند سلول های مختلف موجود در گیاهان و جانوران را شامل می شوند.
0 68 hours ago
It's anatomy review time! I'll go over things that our teacher specifically have mentioned. Also solve some previous exam questions and study the muscles that I took notes on this weekend.
I just learned that the oral part will be 20 minutes and they will ask us questions about different sections that we've learned. I'll go by section this week.
I like to speak to myself and teach myself. I think that makes the information more durable in my brain. I'll use the Complete Anatomy to visualise the 3D anatomy and I highly recommend the app (it's a popular app but just in case you don't know about it). Have a great week!
May the odds be in your favor!
The walking protein “kinesin”
It’s of the proteins that I was in love with when I was taking cell biology course. So what is this protein?
Kinesins move along microtubule (MT) filaments, and are powered by the hydrolysis of adenosine triphosphate (ATP) (thus kinesins are ATPases). The active movement of kinesins supports several cellular functions including mitosis, meiosis and transport of cellular cargo, such as in axonal transport. Most kinesins walk towards the positive end of a microtubule, which, in most cells, entails transporting cargo such as protein and membrane components from the centre of the cell towards the periphery. This form of transport is known as anterograde transport.
The importance of science communication. It is as simple as that.
3 1511 hours ago
#IYPT2019 1: Hydrogen
Element number one in the periodic table: hydrogen (H) is where it all starts!
The first element ever to formed after the big bang, and the most abundant in our universe! Roughly 75% of the universe (by weight) is hydrogen including our sun (swipe right)! Did you know: Inside the sun, a VERY LARGE amount (approx 600,000,000 tonnes per second!) of hydrogen is consumed in nuclear fusion where 2 H becomes 1 Helium, to produce most of the light and heat we need to survive!
H is placed in the top left of the periodic table in the same group as the alkali metals (including lithium, sodium and potassium) which are metals (duh) and react explosively with water.
But wait, isn’t hydrogen a non-metal, and a gas?
Correct! It also doesn’t react badly with water, however it does have some similar properties to the alkalis, such as:
- bonding with the halogens (in group VII) such as hydrogen + chlorine = hydrochloric acid (H + Cl -> HCl)
- Same outer valence shell occupancy (huh? - the outermost shell which houses electrons in all the elements in this group is an “s” orbital and only contains 1 electron)
But overall, hydrogen has some very individual properties, so maybe should be put in a group all of its own (and sometimes it is depicted that way for this reason?)
Don’t forget to let me know what elements you want me to cover in this series!
Images adapted from Theodore Gray’s ‘Elements Vault’.
I had the privilege of meeting an absolutely wonderful patient and person today who unfortunately has a leaking corneal perforation in one of his eyes. At this stage, the only current treatment available is a corneal transplant. However, with his age and an at best average outcome even with the transplant, it was difficult to justify that plan of action.
It was an absolute privilege and humbling experience to be present as such an intimate exchange between patient and doctor unfolded.
A joint consensus was eventually reached and unfortunately, this eye was lost. He remained positive and vowed to take good care of his remaining eye.
Patients like this remind me of why I do what I do. I know I may only be one person, chipping away slowly in the realm of the unknown, but every scientific contribution and every creative idea that seeks to apply this knowledge brings us baby steps closer to better health outcomes for patients.
I feel so blessed to be in a position where I have the potential to make a difference and I hope that one day, I will be a great ophthalmologist just like my supervisors. Hopefully, when that time comes, we will be able to provide better outcomes for patients than we can now!
It’s live!! In today’s video I talk all about calorie restriction as a way to increase life span. Go and check it out. The link to my channel and the full video is in my bio! Don’t forget to subscribe and let me know your opinion in the comments!!
La formación de órganos y tejidos es uno de los pasos críticos del desarrollo embrionario temprano que depende de arreglos microscópicos celulares. En un estudio de la Universidad de Columbia, se han registrado por time-lapse las migraciones celulares de auto organización que siguen las células troncales embrionarias para formar el tubo digestivo.
Un paso importante en la búsqueda de cuáles son los mecanismos precisos que subyacen a la emergencia de complejidad en la formación de nuestros órganos siguiendo las instrucciones que están codificadas en nuestro ADN.
Q: You have won the lottery, but you are not happy, why?
A: Adaptation level Theory
You have won the lottery, but adaptation level theory suggests that due to the contrast from your current life to your old life and your habituation- the new money will not make you as happy as you thought. But why?
1.Money creates contrast. The new shiny experience you get with money are found to lessen the impact of ordinary pleasures,
2. Habituation, in this case becoming accustomed to the pleasures of wealth will eventually reduce the value of these new pleasures and as a result diminish the happiness associated with this new lifestyle.
Who is cultured?
Cultured is a communication science platform cultivated by two registered biomedical scientist. Cultured is a bridge between the breakthrough scientific technology of today and you. YOU have important choices to make and cultured is the bank of facts to assist in you in making these choices.
Subject area's include;
Welcome to the world, we hope to open your eyes.
‘wealthy people do not necessarily obtain enjoy happier lives’
Happiness is subjective and relative to the individual. However happiness can be measured using the ‘Cantril Ladder’, a scale created by psychologist Hadley Cantril. The imaginary ladder has 10 rungs, with rung no.1 representing the subjects worst life imaginable, and run 10 being their subjects most optimal life. The subjects are asked to identify the rung number which they consider reflects their past, present of future life. Using this Cantril Ladder, scienctist have asked the question, 'can money buy happiness?'. As money and wealth are considered the outcomes of success, giving people the ability to make new choices, it is not surprising that countries with a higher GDP are considered to home happier people. However, Richard Easterlin, a professor of economics at the University of Southern California, has observed an odd paradox involving money and happiness. Easterlin has concluded that wealthy people within countries tend to be happier than the poorest in the same country, but overall, more wealthy countries are no happier than their poorer ‘third world’ counterparts. These findings, known as the Easterlin paradox, conclude wealthy people do not necessarily have happier lives.
Can we stop 🛑 ageing? ⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀⠀⠀⠀⠀⠀⠀⠀⠀
My latest #ScienceScribbles tutorial will be available on my YouTube channel tomorrow - link in bio! ⠀⠀⠀⠀⠀⠀⠀⠀⠀
If you want to find out what scientists 👩🏼🔬 have been doing to try and stop ✋🏻 ageing 👵🏻 then make sure you look out 👀 for tomorrow’s upload!
11 1412 days ago
Health Benefits of the Dead Sea:
1. The dead sea is 423 metres below sea level, making it the lowest point on earth. The increased barometric pressure from this decrease in altitude produces atmospheric conditions beneficial for asthmatics
2. Individuals with the skin disease psoriasis find relief in Dead Sea's mineral-rich water and mud and intense middle eastern sun. In recent times, health companies and charities fund skin diseased people to come on therapeutic trips to the dead sea.
2 212 days ago
The Dead Sea is Dying.
The Dead Sea, the salty lake located at the lowest point on Earth bordered by Jordan to the east and Israel and the West Bank to the west. The lake is shrinking by more than 1m annually due to soaring global warming pushing temperatures. The 2019 crisis, how do we find extra water to sustain the life that relies on the dead seas pool?
1 122 days ago
Orion correlation theory:
The Orion correlation theory hypothesizes that there is a correlation between the location of the three largest pyramids of the Giza and the constellation Orion's Belt and that this correlation was intended by the pyramid original builders. Accompanying this theory, the Nile river is hypothesized to reflect the Milky Way galaxy.
2 122 days ago
'The effect of pyramids on microorganisms'
by Itagi Ravi Jumar, N V C Swamy and H R Nagendra.
This research has found that the when milk samples are placed inside a Pyramidal structure, less microorganism growth is found than those kept in other square shaped structures- a theory used to ensure mummies stay preserved for centuries. Ancient egyptions were manipulating geometrey and had an understanding of bacteriaal growth as far back as 2500BC.
2 112 days ago
The wild Bactrian camel is considered critically endangered by the International Union for Conservation of Nature and has a population that is decreasing, now at fewer than 1,000 wild camels alive.
How to help?
The habitat of Central Asia is largely destroyed by cattle animal agriculture. Global warming is also threatening wild Bactrian camels by making living conditions more extreme and lessening the number of area's theses cammels can surivive in. The single largest combatting strategy against climate change in reducing meat consumption to preserve habitat against farming practises.
Conservation efforts: Two large Gobi desert reserves with an encorpated breeding program has been emplaced for the species by the Chinese and Mongolian governments and the Wild Camel Protection Foundation.
2 182 days ago
New quilt? Deconstructed lab coat, doodles and old data slides. Waiting for the spark. #cell#cellbiology
3 116 days ago
Popular Instagram Photos
Finally back in the lab 🥼 ⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀⠀⠀⠀⠀⠀⠀⠀⠀
And after moaning that January had been a bit slow in my previous post, today I’ve been informed that there are 5 participants lined up for next week. ⠀⠀⠀⠀⠀⠀⠀⠀⠀
FIVE in ONE week 😱!
This means next week is going to be very busy for me. And if the rest of the year continues like this pretty soon I’ll be drowning in data 📈📊, which I’m definitely not complaining about 😊!
18 14344 days ago
Spying 🕵🏼♀️ on the cells I resurrected last week! Looks like they survived the freeze thaw 🙌🏻!
Genetic information has to be passed down from one generation to another. Before cell duplication, the original DNA molecule is copied and splitted to each daughter cell. Not a simple task! The enzyme that duplicate the DNA molecule is called DNA polymerase. DNA polymerase follows the Watson and Crick base pairing rule, i.e. A pairs with T, G pairs with C. DNA replication is semiconservative. Each strand of the double helix acts as template for the synthesis of new complementary DNA. Once the helicase unwinds the double helix, DNA polymerase runs along the DNA filament adding nucleotides to the 3’ end of a DNA strand, moving from 5’ → 3’ direction. Due the antiparallelic nature of the double helix (one filament goes from 5’ → 3’, the complementary goes from 3’ → 5’), the two new strands are synthetized in a different way. The leading strand, which is complementary to the 3’-5’ parental strand, is synthetized as a continuous piece of DNA. On the other hand, the lagging strand, complementary to the 5’-3’ strand, has to be synthetized as a small fragments, called Okazaki fragments, which are then sealed together by a protein called DNA ligase. However, DNA polymerase can be error-prone and then bypass a lesion in the double helix keeping writing the DNA, or have proof-reading activity, i.e. they can repair a wrong base pairing. For this, DNA polymerases are critical to mantain DNA stability. @sci_comm original text.
L'enzima che duplica il DNA è la DNA polimerasi. La DNA pol. accoppia A con T, G con C. La replicazione del DNA è semi-conservativa. Ogni filamento della doppia elica funge da stampo per la sintesi di nuovo DNA. La DNA pol. scorre sul filamento di DNA aggiungendo nucleotidi all'estremità 3' di un filamento di DNA, spostandosi in direzione 5' → 3 '. A causa della natura antiparallelica della doppia elica (un filamento va da 5 '→ 3', il complementare va da 3 '→ 5'), i due nuovi filamenti sono sintetizzati in maniera differente. In presenza di un errore, le DNA polimerasi possono o bypassarli o correggerli. Per questo, la DNA polimerasi è fondamentale per mantenere la stabilità del DNA.