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Nikola, Krista, Violeta, Džesika, Angeline

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Jasmīne, Samanta Marija, Endija, Sabīne L., Daniela

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Eduards, Edvards, Haralds, Nauris

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Kam jābūt uz Padlet sienas un kas būs ar to jādara?
(1) 5 minūšu prezentācija par grupai iedalīto dzīvo organismu valsts šūnas analīzi (iekļauti piemēri un papildus informācija).
(2) Pēc prezentācijas vai prezentācijas laikā katrai grupai jāuzdod 3 jautājumi klasesbiedriem.

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Baktērijas šūnas (prokariotu šūnas)- vienšūnas organismi, kam atšķirībā no eikariotiem nav kodola un ar membrānu norobežotu sūnas organoīdu.

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Šūnas shematisks bioloģisks zīmējums.

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DNS- satur šūnas informāciju
Plazmīda- satur papildus gēnus, kas noder, piemēram, replikācijā
Skropstiņas- nodrošina sūnas pārvietošanu
Ribosomas- sintizē šūnai nepieciešamās olbaltumvielas
Citoplazma- saista šūnas komponentus, nodrošina šūnas vielmaiņu
Vica- nodrošina šūnas pārvietošanos
Membrāna- veic vielu transportu, puscaurlaidīga
Šūnapvalks- piedod šūnai formu un pasargā to no ārējās vides
Gļotu kapsula- dod šūnai papildus aizsardzību

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Vakuola
Plazmatiskā membrāna
Šūnapvalks
Ribosoma
Lizosoma
Šūnapvalka starpsienas
Kodols
Endoplazmatiskais tīkls
Mitohondrijs
Goldži komplekss

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Vienšūņi jeb protozoji ir nelieli, kustīgi, dzīvniekiem līdzīgi organismi.

Vienšūņi ir eikarioti - to šūnās ir kodols un citi ar membrānu norobežoti organoīdi. Vienšūņiem ir dažas šūnas sastāvdaļas, kas nav citiem.

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Paņemts no akvārija. (Mitrās vietās baktērijas vieglāk saskatīt un tām vieglāk attīstīties)

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Bacteria Under a Microscope (1000x - 2500x)

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Vienšūņi sastāvā ir:

Plazmatiska membrāna- barjera starp citoplazmu un ārējo vidi. Aptver arī izvirzītās struktūras, piemēram, skropstiņas.

kodols- satur ģenētisko šūnas informāciju (DNS)

citoplazma - pusšķidra viela, kas veido šūnas iekšējo vidi, tajā tiek šķīdinātas un pārvietotas dažādas vielas.

mutes atvere - caur to uzņemtā barība nonāk barības vakuolās.

pulsējošā vakola -kontrolē ūdens balansu , uzkrājot un izvadot lieko ūdeni no šūnas, ļaujot šūnām izdzīvot stresa apstākļos kā, piemēram,dīķa ūdenī.

lizosoma - atbild par makromolekulu, veco šūnu daļu un mikroorganismu gremošanu.

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Baktēriju šūnas organismi ir gan autotrofi, gan heterotrofi.

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Pēc formas baktērijas iedalās nūjiņveida (2), lodveida (1) un spirālveida (3) baktērijās.

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1. Izraisa slimības
2. Palīdz pārstrādāšanas procesā
(Gan videi, gan cilvēka gremošanā)
+ izmanto ražošanā (ēdiens, medikamenti utt.)

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INFORMĀCIJU UN TĀS NOZĪMĪGUMU IZVĒLATIES PAŠI (iesaku padomāt par uzbūvi, daudzveidību, kādu piemēru, kā atšķirt no citām šūnām u.tmldz.)

(1) Iekļaut šūnas bioloģisko zīmējumu (shematiski), kā arī atrast mikroskopa attēlu (norādīt palielinājumu, mikroskopa veidu).
(2) Atrast kādu interesantu faktu (balstīt zinātniskajā pētījumā/rakstā).
(3) BŪS JĀVEIDO ŠŪNAS MODELIS (no otrreizēji izmantojamiem materiāliem).

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Kodols- ieskauj divas membrānas, strap kurām atrodas kodola sula, kurā iekšā atrodas kodoliņš.

Funkcija- satur DNS, regulē šūnas darbību.

Kodoliņš- atrodas kodola sulā, nav membrānas, sastāv no DNS, RNS, olbaltumvielām un ribosomām.

Funkcija- veido ribosomas

Vakuola- neliels šūnsulas pildīts pūslītis, kuru apskauj membrāna, dzīvnieku šūnās maz.

Funkcija- uzkrāj barības vielas, regulē šūnas spiedienu.

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Graudainais endoplazmatiskais tīkls - tīkla veida organoīds, uz kā membrānas (citoplazmas pusē) atrodas ribosomas.

funkcijas: Olbaltumvielu sintēze. Pārveido jaunsintizētās olbaltumvielas par funkcionējošām olbaltumvielām no pirmējās struktūras.

Ribosomas- ļoti mazi organoīdi, kuri sastāv no olbaltumvielām un nukleīnsākbēm.

funcijas: sintizē olbaltumvielas.

Gludais endoplazmatiskais tīkls- atšķiras ar to, ka tam citoplazmas pusē nav ribosomu.

funkcijas: lipīdu sintizēšana.

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Mitohondrijs - Ar divām membrānām klāts šūnas organoīds. Iekšējā membrāna veido krokas – kristas. Iekšienē ir šķidra vide ar ribosomām, DNS, enzīmiem.

funkcijas -Mitohondriju galvenā funkcija ir ATP ( adenozīntrifosfāts ) molekulu veidošanās, kuru šūnas izmanto, lai nodrošinātu enerģiju sintēzes reakcijām un citiem enerģiju tērējošajiem procesiem.

Goldži komplekss - Goldži komplekss sastāv no plakanu membrānu maisiņu jeb cisternu grupām. Viena cisternu grupa tiek saukta par Goldži ķermenīti. Goldži ķermenīšu skaits dažādās šūnās ir atšķirīgs.

funkcijas - Uzkrāj ET sintezētās vielas un transportē tās pūslīšu sastāvā. Pūslīši izdala vielas ārpus šūnas vai veido lizosomas.

Lizosomas - ar membrānu apņemti pūslīši, kas satur dažādus gremošanas enzīmus.

funkcijas - sagremo šūnā iekļuvušās baktērijas un vīrusus, sagremo bojā gājušos vai novecojušos šūnas organoīdus, kā arī novecojušas šūnas.

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Sēņu šūnas ir eikariotu šūnas.

Sēņu šūnām ir divi morfoloģiskie pamatveidi: īstās hifas (daudzšūnu pavedienveida sēnes) vai raugi (vienšūnu sēnes).

Sēņu šūnu sienas ir stingras un satur polisaharīdus, ko sauc par hitīnu (pievieno strukturālu izturību) un glikānus.

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Augu šūnas ir eikariotiskas šūnas, kas daļēji atšķiras no citu eikariotisko organismu šūnām.

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Plazmatiskā membrāna- sastāv no lipīdu molekulu dubultslāņa, kurā “peld” olbaltumvielu molekulas.

funkcijas- norobežo šūnu no ārvides,nodrošina vielu apmaiņu starp citoplazmu un vidi, uztver un reaģē uz izmaiņām apkārtējā vidē.

Citoplazma- sastāv no hialoplazmas, organoīdiem, citoskeleta un ieslēgumiem. Tā aizņem šūnas telpu starp plazmatisko membrānu un kodolu.

funkcijas- nodrošina vielmaiņu šūnā un mijiedarbību starp organoīdiem.

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Kā atšķirt augu šūnu no dzīvnieku šūnas?

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Kā atšķirt augu šūnu no dzīvnieku šūnas?

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- Augu šūnās ir hloroplasti, bet dzīvnieku šūnām tādas nav.

- Augu šūnu no ārpuses apņem šūnapvalks, bet dzīvnieku šūnu membrāna.

- Augu šūnām vakolas ir lielas, bet dzīvnieku šūnām mazas.

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centrosome - composed by two centrioles and a microtubule organizing center

- located in the cytoplasm near the nucleus

functions -  important role in cell division ; creation and organization of fibers responsible for the movement of the chromosomes

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Vakuola, ko ietver membrāna.
Vakuola ir šūnas lielākais organoīds, kas var aizņemt līdz pat 80% šūnas tilpuma.
Šūnapvalks, ko pamatā veido celuloze, hemicelulozes, pektīns, lignīns un olbaltumvielas.
Plastīdas — hloroplasti, hromoplasti un leikoplasti.

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Vienšūņi dzīvo visās ūdenstilpēs, mitrā augsnē, augos, dzīvniekos un cilvēkos.

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Vienšūņi barojas heterotrofi- enerģiju un barības vielas iegūst no organiskām vielām.
Viņi fagocitozes veidā uzņem un sagremo organiskās vielas un mikroorganismus.

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https://youtu.be/pvOz4V699gk

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Amoeba eats two paramecia (Amoeba's lunch)

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Augu šūnām raksturīga hloroplastu klātbūtne, kas atrodami arī noteiktās aļģēs. Hloroplasts ir plastīda veids, kas kalpo kā fotosintēzes vieta.

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Hifa - gara, zarota, pavedienveida sēnītes struktūra, kas ir galvenais veģetatīvās augšanas veids.
Starpsiena - šūnu sienas dalījums starp sēnīšu hifām
Glikāns - polisaharīds, kas iegūts no D-glikozes un saistīts ar glikozīdu saitēm.

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Vienšūņa ieelpotais skābeklis caur visu ķermeņa virsmu nonāk tā citoplazmā.
Elpošanas procesā caur visu ķermeņa virsmu izdalās oglekļa dioksīds.

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Sēnes sastāv no pavedieniem, ko sauc par hifām. Atšķirībā no augu šūnām, sēņu šūnās nav hloroplastu vai hlorofila. Sēnes var būt ļoti krāsainas no zaļā toņa līdz melnam.

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Fosfolipīdu molekulu dubultslānis, kurā ir olbaltumvielu molekulas. Nodrošina vielu apmaiņu starp citoplazmu un vidi.

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Citoplazmas ar divām membrānām norobežota šūnas sastāvdaļa, kas satur hromatīnu. Regulē šūnas darbību. Kodoliņā veidojas ribosomu sastāvdaļas, kas caur kodola porām nonāk citoplazmā

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Šūnas „ķermenis”, kas sastāv no šķidras iekšējās vides un organoīdiem. Nodrošina vielmaiņu šūnā un mijiedarbību starp organoīdiem.

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Vienšūņi galvenokārt vairojas bezdzimumiski – bināri daloties, pumpurojoties vai daudzkārši daloties.

Dzimumvairošanās notiek ar dzimumšūnu palīdzību. Vienšūņiem viss ķermenis pārvēršas par gametu un gametu saplūšanu sauc par kopulāciju.

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Ļoti mazs organoīds, kas sastāv no divām daļām.  Sintezē olbaltumvielas.

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Ir trīs veida vienšūņi. Tos iedala atkarībā no to pārvietošanās veida.

Vicaiņi- piemēram, zaļā eiglēna. Tie parvietojās izmantojot, kustinot savu vicu.

Skropstaiņi- piemēram, stentors, savām kustībām izmanto skropstiņas.

Sakņkāji- piemēram, amēba, izbīda izaugumus - māņkājiņas un izmanto tās, lai pārvietotos.

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No membrānām veidota cisternu un caurulīšu sistēma. Graudainais ET veic olbaltumvielu sintēzi, pārveidošanu un transportu. Gludais ET sintezē lipīdus.

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Plakanu cisternu un pūslīšu sistēma. Uzkrāj ET sintezētās vielas un transportē tās pūslīšu sastāvā. Pūslīši izdala vielas ārpus šūnas vai veido lizosomas.

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Ar membrānu norobežots šūnas organoīds, kurā ir šķeļošie enzīmi. Dažādu vielu un novecojošu šūnas struktūru sadalīšana

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Ar divām membrānām klāts šūnas organoīds. Iekšienē ir šķidra vide ar ribosomām, DNS, enzīmiem.

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Pasaulē lielākā sēne ir 2400 gadus veca un ir 8901 km plata
Pasaulē ir nezināmi 90% no 3.8 miljoniem sēņu.
Medicīniskā daļa sēnēm ir šūnapvalks

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Augu šūna zem mikroskopa palielinājumā 100x

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Augu šūna zem mikroskopa palielinājumā 100x

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https://youtube.com/shorts/JECKEeThJDk?feature=share

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Chloroplast Flowing Inside the Plant Cell under 100X Len of A Microscope

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Chloroplast Flowing Inside the Plant Cell under 100X Len of A Microscope

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Vienšūņu nozīme un to ietekme uz cilvēku un dzīvnieku organismiem. 

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Vienšūņu nozīme un to ietekme uz cilvēku un dzīvnieku organismiem. 

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Vienšūņiem ir liela nozīme. Piemēram, tupelītes attīra ūdeni, aprijot daudz baktēriju.
Vienšūņi noder arī par barību zivju mazuļiem un citiem dzīvniekiem.
Daudzi vienšūņi cilvēkos un dzīvniekos izpaušas kā parazītiskas šūnas, proti, izraisa slimības un iekaisumus.

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Baktērijas ļoti ātri vairojas. Piemēram, zarnu nūjiņa labvēlīgos apstākļos dalās ik pēc 10 - 20 minūtēm.

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Jau pārliecinājāmies, ka baktērijas nav tikai sliktas kas padara mūs slimus...

Viens interesants fakts ko zināt par baktērijām - tās tieši palīdz cīnīties pret vīrusiem.

Šo dziļāk iespējams papētīt šajā zinātniskajā rakstā https://sciencejournalforkids.org/wp-content/uploads/2021/08/wolbachia-article-MS-level.pdf

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Dzīvnieku šūnas var peldēt, kad vajag.

Šūnas pašas sevi iznīcina, ja tām ir kāds bojājums/ tās apraud citas šūnas.

Šūnas sastāvā 70% ir ūdens.

Dzīvnieku šūnai nav šūnapvalks.

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Vislielākais augs uz zemes ir Posidonia australis, kas pazīstams arī kā šķiedru nezāle vai lentveida nezāle, 4500 gadu veca jūraszāle izplatījusies 200 kvadrātkilometru zemūdens jūras dibenā.

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About 4,500 years ago, a single seed - spawned from two different seagrass species - found itself nestled in a favourable spot somewhere in what is now known as Shark Bay, just off Australia's west coast.

Left to its own devices and relatively undisturbed by human hands, scientists have discovered that seed has grown to what is now believed to be the biggest plant anywhere on Earth, covering about 200 sq km (77 sq miles, or about 20,000 rugby fields, or just over three times the size of Manhattan island).

The species - a Posidonia australis, also known as fibre-ball weed or ribbon weed - is commonly found along the southern coastlines of Australia.

But when scientists started looking for genetic differences in ribbon weed across the bay, they came across a puzzle. Samples taken from sites that were 180km apart suggested there were not multiple specimens of Posidonia australis, but one single plant.

"We thought 'what the hell is going on here?'" said Dr Martin Breed, an ecologist at Flinders University. "We were completely stumped."

Student researcher Jane Edgeloe, of the University of Western Australia (UWA), said about 18,000 genetic markers were examined as they looked for variations in the species that might help them select specimens for use in restoration projects.

But what they found instead was that the same plant had spread using rhizomes in the same way that a lawn can spread from its edges by sending out runners.

"The existing 200 sq km of ribbon weed meadows appear to have expanded from a single, colonising seedling," she said.

The one plant now spreads out like a meadow, providing habitat for a huge array of marine species including turtles, dolphins, dugongs, crabs and fish.

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Ribbon weed rhizomes can grow up to 35cm a year and, using that rate, the authors of the research - published in Proceedings of the Royal Society B - estimate the plant will have needed at least 4,500 years to spread as far as it has.

Dr Elizabeth Sinclair, a co-author of the research at UWA, said they hadn't given the plant a nickname, and original samples - pulled from the seagrass meadow - originally had 116 different labels with GPS coordinates when they were stored in a deep freeze ready for genetic sampling.

The plant has formed huge, dense meadows that in some areas stretch as far as the eye can see in all directions. The ribbons of the plant are only 10cm long in some places, but up to a metre in others.

The plant's spread can be seen in this aerial view of Shark Bay. Photograph: Angela Rossen

Conditions in Shark Bay itself are challenging. The plant has found a way to survive in areas where the salinity is double that elsewhere in the bay, and can thrive in water temperatures as cold as 15C and as hot as 30C.

The seagrass plant's survival appears to be linked, Sinclair said, to how it had held on to all the chromosomes from its two parents, giving it inbuilt genetic diversity.

"Instead of getting half [of] its genes from mum and half from dad, it's kept all of them," she said.

Sinclair and colleagues are still working through the secrets of the giant specimen, but she said it appears to be "largely sterile" and so has to rely on its own ability to grow, rather than disperse seeds.

Breed said the fact the plant "doesn't have sex" but had survived for so long was a puzzle.

"Plants that don't have sex tend to also have reduced genetic diversity, which they normally need when dealing with environmental change," he said.

Breed said they had detected some very subtle mutations in the plant's genetics across the places it was growing that might also explain its extreme longevity.

The size of the Shark Bay ribbon weed is about 20,000 hectares (49,000 acres) - making it much larger than a stand of quaking Aspen trees in Utah, often referred to as the world's largest plant, covering 43 hectares.

Associate professor Kathryn McMahon, of Edith Cowan University, was not involved in the Shark Bay research but is an expert on seagrass. She said the method used by the researchers gave her confidence they had identified one single specimen, which she said was "amazing".

Genetic studies of other seagrass species had estimated the plants could live for between 2,000 and 100,000 years, so McMahon said the estimate that the Shark Bay specimen was 4,500 years old fits into that range.

"They have a versatile growth pattern which contributes to this long life span," she said. "They can grow towards nutrient-rich patches to access the nutrient they need, or to gaps in the meadow where there is space for them to grow or away from stressful locations.

"All of these characteristics mean that if they are in the right place they can persist over long periods of time."

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Scientists discover 'biggest plant on Earth' off Western Australian coast

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About 4,500 years ago, a single seed - spawned from two different seagrass species - found itself nestled in a favourable spot somewhere in what is now known as Shark Bay, just off Australia's west coast.

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Eiglēna zem gaismas mikroskopa ar 1000x palielinājumu. 

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Eiglēna zem gaismas mikroskopa ar 1000x palielinājumu. 

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- Daži vienšūņi spēj inficēt cilvēka smadzenes, ietekmējot cilvēka uzvedību.
Šos vienšūņus uzņem visu veidu dzīvnieki, tostarp suņi, grauzēji un cilvēki, tie inficē muskuļus un smadzenes, lai izvairītos no saimnieka imūnsistēmas uzbrukumiem.
- Protisti bija dominējošā dzīvības forma uz Zemes pirms aptuveni 1,5 miljardiem gadu. Vienšūņi attīstījās agri un ir izdzīvojuši līdz mūsdienām, tāpēc tie neapšaubāmi ir piedzīvojuši ievērojamas evolūcijas izmaiņas. (https://www.britannica.com/science/protozoan/Evolution-and-paleontology)

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THE ANCIENT DEBATE surrounding the existence of free will appears unresolvable, a metaphysical question that generates much heat yet little light. Common sense and volumes of psychological and neuroscientific research reveal, however, that we are less free than we think we are. Our genes, our upbringing and our environment influence our behaviors in ways that often escape conscious control. Understanding this influence, the advertisement industry spent approximately half a trillion dollars worldwide in 2010 to shape the buying decisions of consumers. And extreme dictatorships, such as that in North Korea, remain in power through the effective use of insidious and all-pervasive forms of propaganda. Yet nothing approaches the perfidy of the one-celled organism Toxoplasma gondii, one of the most widespread of all parasitic protozoa. It takes over the brain of its host and makes it do things, even actions that will cause it to die, in the service of this nasty hitchhiker. It sounds like a cheesy Hollywood horror flick, except that it is for real.

We know that illness in general can slow us down, incapacitate us and, in the worst case, kill us. Yet this organism is much more specific. Natural selection has given rise to pathogens that infiltrate the nervous system and change that system's wiring to achieve its ultimate purpose, replication-like a computer virus that reprograms an infected machine.

Such is the case with T. gondii. It sexually reproduces only in the intestines of cats yet can maintain itself indefinitely in any warm-blooded animal. Infected cats shed millions of their oocysts in their feces. Taken up by all kinds of animals, including dogs, rodents and humans, they infect muscle and the brain to escape attacks by the host's immune system. Hidden away, they remain dormant as cysts, surrounding themselves with a tough cell wall. Yet this quiet stage of infection, called toxoplasmosis, is deceptive. Violating all rules of good hospitality, these invaders make the host's brain do things counterproductive to its own survival.

Toxoplasmosis has been most thoroughly studied in rats and mice. Both species have a deep-seated, innate fear of cats for obvious reasons. Spray a bit of cat urine into a corner, and the rodent will avoid this location, well, like the plague. In contrast, an infected animal loses its innate fear of cats. By some measures, it even appears to be mildly attracted to the smell of felines. This is an unfortunate turn of events for the rodent, because it is now more likely to be successfully hunted by a cat. On the other hand, this is a great deal for T. gondii. When the cat devours the sick critter and its contaminated brain, T. gondii moves into its final host, where it reproduces, completing its life cycle. Not quite what the romantics have in mind when they write about "the circle of life"!

The behavioral manipulation induced by T. gondii is quite specific. The infected rodent doesn't look sick; its weight is normal; it moves about normally, possibly a bit more frantically than other mice; it grooms itself; and it interacts routinely with its conspecifics. Think how different this case is from what happens in rabies, another nasty infection. The animal loses its instinctual shyness, aggressively attacking others (the proverbial mad dog), thereby spreading the rabies virus through its bite. But because T. gondii can reproduce only in felines, it wants its host to be eaten by cats, not by just any carnivore. And because cats hunt live prey and do not eat carrion, T. gondii must not immediately kill its temporary host.

Rodents Aren't Superheroes
How does T. gondii effect its insidious changes in the host? Experiments by Joanne P. Webster of Imperial College London, Robert Sapolsky of Stanford University and others have shown that infected rats or mice do not turn into the murine equivalent of Siegfried, the hero of Wagner's Ring who knew no fear. No, they still avoid open spaces, remain nocturnal creatures, retain their aversion to the urine of other predators and learn to fear a tone associated with a foot shock. Might the protozoa have stunted their smell? After all, if they cannot smell anything anymore, they would not know how to avoid places smelling of cat urine. But infected mice still avoid food if it smells different-an aversion that arose partly because for centuries humans have been trying to control rodents by poison. The infected mice also respond appropriately to the smell of their littermates.

Clues about how the parasites affect the animal come from several observations. First, the density of cysts in the amygdala is almost double that in other brain structures involved in odor perception. Parts of the amygdala have been linked to anxiety and the sensation of fear. Second, the genome of T. gondii contains two genes related to mammalian genes involved in the regulation of dopamine, the molecule associated with reward and pleasure signals in the brain, including in ours. So perhaps the creepy protozoa makes suicidal activities, such as hanging around places frequented by cats, feel more pleasurable for the infected rodent?

What elevates this vignette about evolution and life in the wild to epic proportions for humanity is that about a tenth of the U.S. population is infected by T. gondii (in some countries, such as France, the infection rate is seven to eight times higher, possibly because of the widespread consumption of uncooked and undercooked meat). Human toxoplasmosis is usually considered to be symptom-free (what doctors refer to as asymptomatic). Exceptions are patients with a weakened immune system and the unborn (hence the need for pregnant women to avoid cleaning cat-litter boxes).

Science has known for a long time that schizophrenic patients are two to three times more likely to carry antibodies to T. gondii than are controls who are not schizophrenic. Furthermore, antipsychotic drugs that block the action of dopamine, such as haloperidol, commonly used in the treatment of schizophrenia, are also effective in combating toxoplasmosis in both rats and people. And some infected adults go on to develop psychotic symptoms similar to schizophrenia. Little is known about the mode or site of action of this pathogen in the human brain. The exact link between T. gondii and psychiatric diseases is tantalizing but remains murky.

Recent claims go so far as to argue for a role of T. gondii in shaping distinct cultural habits, depending on the rate of infection in the population. A prospective study tracking the road safety in Czech recruits during their 18 months of compulsory military draft found a rate of accidents six times higher in affected drivers. Are the young men with toxoplasmosis infection simply slowed down? Or do they drive more aggressively?

In my November 2009 column, I described the discovery by cognitive neuroscientists that the feeling of freely willing an action (called authorship or agency) is a subjective, conscious sensation no different, in principle, from the conscious awareness of seeing the azure blue sky or feeling the sharp pain of a toothache. When I engage in a dangerous pursuit, such as taking the end of the rope on a steep section of a granite wall in Yosemite Valley while climbing, I feel as if "I freely decided" to do so, whatever this might mean in a metaphysical sense. Yet my action is most likely caused by an inexhaustible multiplicity of factors not accessible to my conscious introspection, including, yes, possibly some tiny single-celled parasites lodging in my brain and making me act out their silent commands. The wonder of it all.

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Protozoa Could Be Controlling Your Brain

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THE ANCIENT DEBATE surrounding the existence of free will appears unresolvable, a metaphysical question that generates much heat yet little light. Common sense and volumes of psychological and neuroscientific research reveal, however, that we are less free than we think we are.

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