Why do functions not work when I call them?

Please, somebody tell me why my functions don't respond when I call them.

In the following code everything works fine:

int nose = 7;

void setup() {

pinMode(nose, OUTPUT);
}

void loop() {

digitalWrite(nose, HIGH);
//turnNoseOn;

delay(500);

digitalWrite(nose, LOW);
//turnNoseOff;

delay(500);
}

void turnNoseOn() {
digitalWrite(nose, HIGH); // turn the LED on
}

void turnNoseOff() {
digitalWrite(nose, LOW); // turn the LED off
}

But if I comment out the digitalWrite statements and use the function calls instead (see below), nothing happens.

I am an experienced programmer but not much with C.

Please tell me what obvious error I am making here.

int nose = 7;

void setup() {

pinMode(nose, OUTPUT);
}

void loop() {

//digitalWrite(nose, HIGH);
turnNoseOn;

delay(500);

//digitalWrite(nose, LOW);
turnNoseOff;

delay(500);
}

void turnNoseOn() {
digitalWrite(nose, HIGH); // turn the LED on
}

void turnNoseOff() {
digitalWrite(nose, LOW); // turn the LED off
}

turnNoseOff; is a function pointer

turnNoseOff(); is a function call

W1KOK:
void loop() {

//digitalWrite(nose, HIGH);
turnNoseOn;

delay(500);

//digitalWrite(nose, LOW);
turnNoseOff;

delay(500);
}

Function calling in C requires () even if there are no arguments. Use:

 turnNoseOn(); 
turnNoseOff();

Thanks!