Ellipses aligned on the same boundary point

Question

I want to create a cascade of ellipses in TikZ. However, with my code, I get the ellipses to have the same center. But what I instead want, is that the ellipses have a common point on their boundary (and not the same center).

Below is my MWE with the concentric ellipses (which I don't want) and after that is an image with my intended outcome.

\documentclass{article}  
\usepackage{tikz}  
\begin{document}

\begin{tikzpicture} 
\draw (0,0) ellipse (1cm and 5cm);
\draw (0,0) ellipse (1cm and 4cm);
\draw (0,0) ellipse (1cm and 3cm);
\draw (0,0) ellipse (1cm and 2cm);
\draw (0,0) ellipse (1cm and 1cm); 
\end{tikzpicture}
\end{document}

Answer 1

This is a starting point:

\documentclass[tikz,margin=3mm]{standalone}
\begin{document}

\begin{tikzpicture} 
\draw (0,0) arc (-90:270:1cm and 0.5cm);
\draw (0,0) arc (-90:270:1.5cm and 1cm);
\draw (0,0) arc (-90:270:2cm and 1.5cm);
\draw (0,0) arc (-90:270:2.5cm and 2cm);
\draw (0,0) arc (-90:270:3cm and 2.5cm);
\end{tikzpicture}
\end{document}

Answer 2

\documentclass[tikz,border=2mm]{standalone} 
\usetikzlibrary{shapes.geometric}

\begin{document}
\begin{tikzpicture}

\foreach \i/\j in {1/.5, 1.5/.75, 2/1, 2.5/1.25}
\node[ellipse, draw, anchor=south, inner sep=0pt] at (0,0) {\phantom{\rule{\i cm}{\j cm}}};
\end{tikzpicture}
\end{document}