Lissy wrote:

I'm growing several cucumber and courgette plants in my sunny attic
room. I have noticed though that:

a) little cucumbers are growing followed by flowers - do I need to do
some pollinating for them to develop further ? Are the flowers male or
female ???

If you see a small cucumber behind the flower, those are female flowers.
If there are no male flowers, I would hope that you have one of the
varieties that neither produce nor need male flowers for the cucumbers
to form.

b) I have a few courgette flowers, but nothing resembling a courgette.
Do I need to break into these flowers and do some pollination for them
to fruit ???? Is the sex - ie male or female predetermined ???? If so
why do I need to pollinate ????

You need to pollinate because you want the plant to grow something for
you to eat!
If you see no miniature courgette behind the flower (the same as when
you see the small cucumber behind those flowers) , then you are only
getting male flowers so far. (Male flowers often come first on these
plants.) Female flowers come later if the plant is getting enough light
and is doing well other wise. Pollinate the female flowers!

Steve