Answer: Is known as a "heart" shape.
Explanation:
r = 1 + sin(θ)
Let's do it without a graph, let's use only math and logic:
remember that θ is measured from the x-axis
when θ = 0, we have r = 1 (so we have a radius of 1 over the x-axis)
when θ = pi/2, we have r = 1 + sin(pi/2) = 2
when θ = pi, we have r = 1 + sin(pi) = 1
when θ = 3*pi/2, we have r = 1 + sin(3*pi/2) = 0
First, we have symetry around the y-axis,
now, notice that the value of x in θ = 0, θ = pi and θ = 3*pi/2 is the same. so this is not a circle, this is actually a circle where the bottom part is flatted.
But not actually flat, because between θ = pi and θ = 2pi we are in the negative y-axis, so in this region we have two small bumps that connect in the point (0, 0)
This is a kinda "heart" shape.