#include<algorithm>

#include<iostream>

#include<cstdlib>

#include<cstdio>

#include<cmath>

#include<cstring>

using namespace std;

int n,m;

#define MAXN 300010

struct edge

{

	int to,nxt;

}e[MAXN << 1];

int edgenum = 0;

int lin[MAXN] = {0};

void add(int a,int b)

{

	++edgenum;e[edgenum].to = b;e[edgenum].nxt = lin[a];lin[a] = edgenum;

	++edgenum;e[edgenum].to = a;e[edgenum].nxt = lin[b];lin[b] = edgenum;

	return;

}

int in[MAXN][3];

int f[MAXN],g[MAXN];

int get(int x){return (f[x] == 0 ? 0 : (g[x] ^ get(f[x])));}

int find(int x)

{

	if(f[x] == 0)return x;

	int tmp = f[x];

	f[x] = find(f[x]);

	g[x] = g[tmp] ^ g[x];

	return f[x];

}

int top[MAXN],dep[MAXN],siz[MAXN],fa[MAXN],son[MAXN];

void dfs1(int k,int depth)

{

	dep[k] = depth;siz[k] = 1;

	for(int i = lin[k];i != 0;i = e[i].nxt)

	{

		if(e[i].to != fa[k])

		{

			fa[e[i].to] = k;

			dfs1(e[i].to,depth + 1);

			siz[k] += siz[e[i].to];

			if(son[k] == 0 || siz[e[i].to] > siz[son[k]])

			{

				son[k] = e[i].to;

			}

		}

	}

	return;

}

void dfs2(int k,int tp)

{

	top[k] = tp;

	if(son[k] == 0)return;

	dfs2(son[k],tp);

	for(int i = lin[k];i != 0;i = e[i].nxt)

	{

		if(e[i].to != fa[k] && e[i].to != son[k])

		{

			dfs2(e[i].to,e[i].to);

		}

	}

	return;

}

int LCA(int a,int b)

{

	while(top[a] != top[b])

	{

		if(dep[top[a]] < dep[top[b]])swap(a,b);

		a = fa[top[a]];

	}

	return dep[a] < dep[b] ? a : b;

}

#define MOD 1000000007

typedef long long ll;

ll power(ll a,int b)

{

	ll res = 1;

	while(b > 0)

	{

		if(b & 1)res = res * a % MOD;

		a = a * a % MOD;

		b = b >> 1;

	}

	return res;

}

int main()

{

	freopen("usmjeri.in","r",stdin);

	freopen("usmjeri.out","w",stdout);

	scanf("%d%d",&n,&m);

	int a,b;

	int cnt = n - 1;

	for(int i = 1;i < n;++i)

	{

		scanf("%d%d",&a,&b);

		add(a,b);

	}

	dfs1(1,1);dfs2(1,1);

	bool tag = true;

	for(int i = 1;i <= m;++i)

	{

		scanf("%d%d",&in[i][1],&in[i][2]);

		in[i][0] = LCA(in[i][1],in[i][2]);//cout << lca << endl;

		int k = in[i][1];

		while(true)

		{

			k = find(k);

			if(dep[k] <= dep[in[i][0]] + 1)break;

			f[k] = fa[k];//cout << k << " " << fa[k] << " " << find(fa[k]) << endl;

			--cnt;

		}//cout << f[740] << endl;

		k = in[i][2];

		while(true)

		{

			k = find(k);

			if(dep[k] <= dep[in[i][0]] + 1)break;

			f[k] = fa[k];//cout << k << " " << fa[k] << " " << find(fa[k]) << endl;

			--cnt;

		}//cout << f[740] << endl;

	}

	for(int i = 1;i <= m;++i)

	{

		if(in[i][0] == in[i][1] || in[i][0] == in[i][2])continue;

		int p = find(in[i][1]),q = find(in[i][2]);

		if(p == q)

		{

			if(get(in[i][1]) == get(in[i][2]))

			{

				tag = false;

				break;

			}

		}

		else

		{

			g[p] = 1 ^ get(in[i][1]) ^ get(in[i][2]);

			f[p] = q;

			--cnt;

		}

	}

	if(!tag)

	{

		puts("0");

	}

	else

	{

		cout << power(2,cnt) << endl;

	}

	fclose(stdin);

	fclose(stdout);

	return 0;

}