Contrast and compare

Predictably, there is absurdity here. The giant watermelon painted on one wall is a token of an Israeli edict banning the depiction of anything containing the colours of the Palestinian flag, even watermelons. Meanwhile in Arab Idol, a collection of 81 figurines representing Palestinian singer Mohammad Assaf, winner in 2013 of the Arab world's version of Pop Idol, there is joy. It's teamed with a pair of video monitors: one shows footage from the final of that competition, the other the Palestinians who gathered in town squares to watch it on large screens. It gives a very different view of the infamous "Arab Street".

In Picasso In Palestine we see hope, too, as Hourani shows a pair of paintings by Swedish artist Jesper Nordahl. These he uses to document the 2009 project of the same name that he himself initiated and which brought a Picasso painting worth £5 million into the West Bank where it was displayed. The loan (from a Dutch museum) was politically fraught and the insurance was a nightmare, but it happened and that's the point of the piece.

Mostly, however, Hourani deals with memory and loss and with the still-spreading ripples caused by the "Nakba", the Arab word for the land grab that occurred in 1948 and the subsequent Palestinian exodus. It translates as "catastrophe". Put those themes and that event foremost in your mind and the show's central work becomes The Biography Of A Plate. It's a nine-panel painting of a very plain plate which had belonged to neighbours of the Houranis prior to the Nakba. It then became a symbol of exile for the family and was later co-opted into a long-running court dispute (28 sessions) involving Hourani's brother, some Israeli settlers and a stramash in a vegetable market in Hebron in 1984. Like the Israeli-Palestinian conflict itself, it's a complicated story.

For her first solo exhibition in Scotland, New York-based Los Angelino Anne Collier presents a series of eight large C-prints at the Modern Institute and reveals her preoccupation to be the gaze - or "perception and representation" as she calls it. It's a concept which has been picked over by artists for centuries, but feminist theorists and female artists have given it a new lease of life in recent decades and it's in that context that Collier's work sits.

If you know your Ingmar Bergman you'll enjoy the still from his 1966 film Persona which greets visitors to the Institute's Aird's Lane premises. It forms part of a work called Woman With A Camera (Persona) and shows Liv Ullmann - or is it Bibi Andersson? It's hard to tell, which is sort of the point of the film - holding a camera to her face and pointing it at the viewer. Collier photographs the photograph on a plain white piece of paper. You can see the shadows where it doesn't sit flush with the surface.

On another wall, a suite of three works show a hand holding a photo of an eye, the same hand arranging the photo on a blank page of a ring-bound photo album, then the album itself with the photo in place. The partner to the Ullmann/Andersson work is a diptych, Woman With A Camera (Postcard, Verso Recto), which shows the front and back of a vintage postcard of a young Kenyan woman, naked except for a bandolier of shell jewellery - and a camera. It's pleasing and well-executed, if not particularly deep.

Form is the subject under discussion at the Dixon Street premises occupied by American gallerist Kendall Koppe in an exhibition which aims to provoke a dialogue between the work of two apparently disparate artists. They are august British ceramicist and arch-Modernist Dame Lucie Rie and, less well-known in this country, US fashion photographer George Platt Lynes.

Koppe shows six works by each artist, with Rie's serene, delicate pots arranged on a dais snaking across the room and Lynes's black and white images hung on the surrounding walls. The second overpowers the first, however, and here's why: the "form" which is the subject of Lynes's camera is the male body and the images are powerfully homoerotic. One model lies naked on a bed and appears to be fellating an older man who is clothed and staring into the camera. This is Lynes and it's a self-portrait of sorts. What's even more amazing is the dates of these images, which run from 1930 (a heavily-tattooed model with a short-back and sides who could have stepped out of a 21st-century fashion shoot) through to the early 1950s. Lynes anticipates Robert Mapplethorpe by a good half century, then.

The exhortation "Now Sing", spelled out in colourful, metre-high letters on the balcony of the Reid Building, is the last you see of Michael Stumpf's work as you leave Glasgow School of Art. Or maybe it's your entree to it, depending on how you arrive at the building. Either way it makes a cheerful overspill from an equally cheerful show which has seen the Glasgow-based German turn two walls of the Mackintosh Museum into slabs of lemon yellow and mottled peach, and clad another in pewter on which the phrase "Looking at you" is picked out in solid-looking letters. These fence in his sculptural works which use steel, denim, calico, bronze and acrylic resin to make over-sized nuts (as in bolts), a giant pink O (Ring, which hangs from the Director's Balcony) and, in what must be one of the least threatening images in the 2014 programme, a pair of stovetop coffee pots in glazed ceramic. They look almost good enough to eat.

Khaled Hourani, CCA, Sauchiehall Street (until May 18); Anne Collier, The Modern Institute, Aird's Lane (until June 7); Lucie Rie And George Platt Lynes, Kendall Koppe, 6 Dixon Street (until May 17); Michael Stumpf: This Song Belongs To Those Who Sing It, Glasgow School of Art (until May 4)